Jaguar V6 / V8 Engine Management #881

Transcription

J A G U A R
S E R V I C E
T R A I N I N G
SERVICE TRAINING COURSE 881
V6 / V8 ENGINE MANAGEMENT
ISSUE ONE
DATE OF ISSUE: 9/2001
This publication is intended for instructional purposes only. Always refer to the appropriate
Jaguar Service publication for specific details and procedures.
All rights reserved. All material contained herein is based on the latest information available at the time of
publication. The right is reserved to make changes at any time without notice.
Publication T 881/01
© 2001 Jaguar Cars
PRINTED IN USA
INSERT TAB FOR AJ26/AJ27
ENGINE MANAGEMENT
SECTION HERE
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
ENGINE MANAGEMENT SYSTEMS
AJ26/27
1
AJ26 / AJ27 OVERVIEW
2
CONTROL SUMMARIES
3
ENGINE CONTROL MODULES
4
EMS PRIMARY SENSING COMPONENTS
5
INDUCTION AIR THROTTLE CONTROL
6
FUEL DELIVERY AND
EVAPORATIVE EMISSION CONTROL
7
FUEL INJECTION
8
IGNITION
9
VARIABLE VALVE TIMING
10 EXHAUST GAS RECIRCULATION (EGR):
NORMALLY ASPIRATED
11 OTHER ECM ENGINE CONTROL AND
INTERFACE FUNCTIONS
12 AJ26 / AJ27 SUPERCHARGED EMS
13 TASK SHEETS
Service Training Course 881
AJ26 / AJ27 ENGINE MANAGEMENT SYSTEMS
Service Training
AJ26 / AJ27 Engine Management Acronyms and Abbreviations:
A
AACV
AAI
A/C
A/CCM
AFR
B
BARO
BTDC
CAN
CCV
CKP(S)
CMP(S)
DLC
DTC
ECM
ECT(S)
EEPROM
EGR
EMS
EOT(S)
EVAP
FI
FP1
FP2
FTP(S)
HC
HO2(S)
IAT(S)
IAT2
IATS2
KS
LED
LEV
‘A’ Bank (Bank 1)
Air Assist Control Valve
Air Assist Fuel Injection
Air Conditioning
Air Conditioning Control Module
Air : Fuel Ratio
‘B’ Bank (Bank 2)
Barometric Pressure (Sensor)
Before Top Dead Center
Controller Area Network
Canister Close Valve
Crankshaft Position (Sensor)
Camshaft Position (Sensor)
Data Link Connector
Diagnostic Trouble Code
Engine Control Module
Engine Coolant Temperature (Sensor)
Erasable Electronically Programmable Read-Only Memory
Exhaust Gas Recirculation
Engine Management System
Engine Oil Temperature (Sensor)
Evaporative Emission Control
Fuel Injection
Fuel pump 1
Fuel pump 2
Fuel Tank Pressure (Sensor)
Hydrocarbon
Exhaust Gas Heated Oxygen (Sensor)
Intake Air Temperature (Sensor)
Intake air temperature 2 (charge air temperature)
Intake air temperature (Sensor) 2 (charge air temperature sensor)
Knock Sensor
Light Emitting Diode
Low Emissions Vehicle
NOTES
1.2
Student Guide
Date of Issue: 9/2001
MAF(S)
MAP(S)
MIL
N/A
NOx
NTC
O2(S)
OBD
ORVR
PP(S)
PWM
RAM
ROM
SC
SCP
TCM
TP(S)
VVT
WOT
Service Training
Mass Air Flow (Sensor)
Manifold Absolute Pressure (Sensor)
Malfunction Indicator Lamp
Normally Aspirated
Nitrous Oxide
Negative Temperature Coefficient
Exhaust Gas Oxygen (Sensor)
On-Board Diagnostics
On-Board Refueling Vapor Recovery
Pedal Position (Sensor)
Pulse Width Modulated
Random Access Memory
Read Only Memory
Supercharged
Standard Corporate Protocol Network
Transmission Control Module
Throttle Position (Sensor)
Variable Valve Timing
Wide Open Throttle
Measurement Values:
B+ Battery voltage
Hz Hertz (cycles per second)
km/h Kilometers per hour
mph Miles per hour
ms Milliseconds
rpm Revolutions per minute
V Voltage
˚C Degrees Celsius
˚F Degrees Fahrenheit
Ω Ohms (resistance)
> Greater than
< Less than
bar Unit of absolute pressure
in. hg. Unit of absolute pressure (inches of mercury)
NOTES
Student Guide
1.3
Service Training
AJ26 / AJ27 EMS OVERVIEW
The AJ26 engine management system was designed for the introduction of the V8 engine to the Jaguar range of vehicles starting with the 1997 model year XK8. A supercharged version was added for 1998 model year.
The AJ27 engine management system is a further development of the AJ26 system designed to meet more stringent
emission control standards and enhance engine performance. The naturally aspirated AJ27 system was introduced
for the 1999 model year; the supercharged AJ27 system was introduced for the 2000 model year.
System application is as follows:
Engine Management System
Model Year
Models
AJ26
1997
1998
1999
XK N/A
XK & XJ N/A
XJR (SC)
AJ27
1999
2000
2001
2002
XK & XJ N/A
XK & XJ N/A and SC
XK & XJ N/A and SC
XK & XJ N/A and SC
Both systems are built around a two-microprocessor based Engine Control Module (ECM). The ECM is linked to and communicates with other powertrain control modules and other vehicle systems via the Controller Area Network (CAN).
The ECM governs all engine operating functions including:
• Air induction via an electronically controlled throttle
• Fuel delivery
• Sequential fuel injection
• Ignition via on-plug ignition coils
• Idle speed control
• Exhaust emission control
• Evaporative emission control
• Intake valve timing
• Exhaust gas recirculation (certain variants only)
• Cooling system radiator fan control
• Air conditioning compressor control
• Cruise control
• Engine speed limiting
• Engine torque reduction to aid transmission shift quality and enhance traction / stability control
• EMS and OBD II diagnostics
• Default operating modes including engine speed and throttle limits
NOTES
1.4
Student Guide
Service Training
System Variant Summary (North America specification vehicles):
FUNCTION
AJ26 N/A
AJ26 SC
Electronically controlled throttle
• Electronically controlled throttle with mechanical guard
• Full authority electronically controlled throttle
X
X
Variable valve timing
• Two position variable intake valve timing
• Linear variable intake valve timing
X
Exhaust gas recirculation
X*
X
Oxygen sensors
• Upstream HO2S; downstream O2S
• Upstream Universal HO2S; downstream HO2S
X
X
Ignition coils
• A Bank / B Bank ignition coil modules
• Individual integral ignition coil modules
X
Security engine management immobilization
X **
On-board refueling vapor recovery
X ***
AJ27 N/A
AJ27 SC
X
X
X
X
X
X
X
X
X
X
X
X
X ***
X
X
Air assisted fuel injection
X
DTC memory
• DTCs and system adaptions stored in volatile memory
• DTCs and system adaptions stored in non-volatile memory
X
X
X
X
* Early production only. EGR deleted on normally aspirated engine as a running change during 1997.
** Key transponder security input and diagnostic introduced for 1998 model year.
*** On-board refueling vapor recovery (ORVR) introduced for 1998 model year XJ8, 1999 model year XK8.
NOTES
Student Guide
1.5
Service Training
AJ26 / AJ27 EMS OVERVIEW
PWM (Pulse Width Modulated) Control
Pulse width modulated control is an electronic means of switching a control signal ON / OFF to a control device such as
a hydraulic pressure control solenoid so that it can be positioned as necessary to achieve a required hydraulic pressure.
In order for the solenoid to be positioned somewhere between fully closed and fully open to achieve the required
hydraulic pressure, the control signal to the solenoid must be controlled in a way that allows infinite positioning
between closed / open.
Frequency
With pulse width modulation, the control signal to the solenoid is switched ON and OFF very quickly at a frequency
(cycles per second) normally expressed in Hertz (Hz). An average frequency for automotive application is approximately 300 Hz.
Duty cycle
DUTY CYCLE
The length of time the control signal is switched ON
during each cycle (pulse width) is varied by the control
module and referred to as the duty cycle, normally
expressed as a ratio percentage between 0 and 100.
The duty cycle will determine the position of the solenoid because the solenoid cannot follow the rapid on /
off control signal and assumes a position between the
limits of travel proportional to the duty cycle.
PULSE WIDTH
ONE CYCLE (Hz)
Pulse width
T880/109
Only the pulse width is varied by the control module.
The frequency usually remains fixed with PWM controlled devices.
NOTES
1.6
Student Guide
Positive / Negative Duty Cycle
Service Training
POSITIVE / NEGATIVE DUTY CYCLE
The control signal can be either a power supply or
ground. If the control signal is a power supply, the duty
cycle is determined as the high voltage pulse (positive
pulse). If the control signal is a ground, the duty cycle is
determined as the zero voltage pulse (negative pulse).
Before measuring or monitoring a PWM signal, first
determine if the signal should be a positive or negative
duty cycle.
1 Hz
B+V
50%
HIGH
50%
LOW
50% DUTY CYCLE
0V
B+V
25%
HIGH
75%
LOW
25% POSITIVE DUTY CYCLE
75% NEGATIVE DUTY CYCLE
0V
T880/110
NOTES
Student Guide
1.7
1.8
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
CONTROL SUMMARIES
The AJ26 and AJ27 engine management systems are comprehensive engine control systems that allow complete
electronic control over all engine functions. The following eight pages provide control summaries for the four system variants. Specific pin-out data can be found in the applicable Electrical Guide.
System Logic: AJ26 N/A
AJ26 N/A ENGINE MANAGEMENT SENSORS AND COMPONENTS
IATS
MECHANICAL GUARD
SENSOR
PEDAL POSITION
SENSOR
MAFS
TPS
THROTTLE
MOTOR
M
IGNITION
MODULE
1
CYLINDERS
1A, 2B, 3B, 4A
IGNITION
MODULE
2
CYLINDERS
1B, 2A, 3A, 4B
EGR
CMPS
FI
FI
IGNITION
MODULE
IGNITION
MODULE
VVT
VVT
ECTS
KS
HO2S
HO2S
A BANK
B BANK
O2S
O2S
CKPS
T880.01
2.2
Student Guide
Service Training
AJ26 N/A ENGINE MANAGEMENT INPUTS / OUTPUTS
FUEL PUMP
RADIATOR FANS
A/C COMPRESSOR
CLUTCH
FUEL PUMP
RELAY
RADIATOR
FAN CONTROL
RELAY MODULE
A/C COMP.
CLUTCH
RELAY
BATTERY POWER
IGNITION SWITCHED
POWER
ECM SWITCHED POWER
EMS
CONTROL
RELAY
BATTERY POWER
MAFS
BARO
IATS
FUEL INJECTOR
POWER SUPPLY
ECTS
FUEL
INJECTION
RELAY
BATTERY POWER
IGNITION
COIL
RELAY
BATTERY POWER
ECM SWITCHED
POWER
CKPS
IGNITION
POWER SUPPLY
CMPS
HO2S
O2S
ECM SWITCHED POWER
KS
THROTTLE
MOTOR
POWER
RELAY
ECM SWITCHED
POWER
BATTERY POWER
THROTTLE
FUEL INJECTORS
A/C REFRIGERANT
4-WAY
PRESSURE
SWITCH
CPU 1
IGNITION
MODULES
CRUISE
CONTROL
SWITCHES
HO2S HEATERS
VARIABLE
VALVE TIMING
EVAPP
PARKING
BRAKE
SWITCH
EGR
VACUUM SWITCHING
VALVES
BPM (ENGINE CRANK SIGNAL)
DIAGNOSTIC
MONITORING
CPU 2
TRANSMISSION (PARK / NEUTRAL)
SECURITY INTERFACE
SERIAL COMMUNICATION
DATA
ENGINE CONTROL MODULE
CAN (NETWORK):
• ABS/TCCM
• TCM
• GEAR SELECTOR ILLUMINATION
• INSTRUMENT PACK
T880.02
Student Guide
2.3
Service Training
CONTROL SUMMARIES
System Logic: AJ26 SC
AJ26 SC ENGINE MANAGEMENT SENSORS AND COMPONENTS
IATS
MECHANICAL GUARD
SENSOR
PEDAL POSITION
SENSOR
MAFS
TPS
THROTTLE
MOTOR
M
EGR
FI
IGNITION
MODULE
1
CYLINDERS
1A, 2B, 3B, 4A
IGNITION
MODULE
2
CYLINDERS
1B, 2A, 3A, 4B
FI
IATS 2
IGNITION
MODULE
ECTS
CMPS
IGNITION
MODULE
KS
HO2S
HO2S
A BANK
B BANK
O2S
O2S
CKPS
2.4
Student Guide
T880.03
Service Training
AJ26 SC ENGINE MANAGEMENT INPUTS / OUTPUTS
FUEL PUMP 1
FUEL PUMP 2
CHARGE AIR
COOLER PUMP
FUEL PUMP
1
RELAY
FUEL PUMP
2
RELAY
CHARGE AIR
COOLER
PUMP RELAY
RADIATOR
FANS
A/C
COMPRESSOR
CLUTCH
RADIATOR
FAN
CONTROL
RELAY MOD.
A/C COMP.
CLUTCH
RELAY
BATTERY POWER
IGNITION SWITCHED POWER
ECM SWITCHED
POWER
EMS
CONTROL
RELAY
MAFS
BATTERY
POWER
IATS 2
ECTS
FUEL
INJECTOR
PWR SUPPLY
BARO
CKPS
FUEL
INJECTION
RELAY
CMPS
IGNITION
PWR SUPPLY
HO2S
IGNITION
COIL
RELAY
O2S
ECM SWITCHED
POWER
KS
IATS
THROTTLE
MOTOR
POWER
RELAY
BATTERY
POWER
ECM
SWITCHED
POWER
BATTERY
POWER
ECM
SWITCHED
POWER
BATTERY
POWER
FTP SENSOR
A/C REFRIGERANT
4-WAY
PRESSURE
SWITCH
THROTTLE
CPU 1
CRUISE
CONTROL
SWITCHES
FUEL
INJECTORS
IGNITION
MODULES
BRAKE
SWITCH
HO2S
HEATERS
EVAPP
PARKING
BRAKE
SWITCH
CCV
EGR
VACUUM
SWITCHING
VALVES
CPU 2
DIAGNOSTIC
MONITORING
SECURITY INTERFACE
DATA
CAN (NETWORK):
• ABS/TCCM
• TCM
• INSTRUMENT PACK
T880.04
Student Guide
2.5
Service Training
CONTROL SUMMARIES
System Logic: AJ27 N/A
AJ27 N/A ENGINE MANAGEMENT SENSORS AND COMPONENTS
IATS
MAFS
PPS
AACV
TPS
THROTTLE
MOTOR
M
FI
FI
CMPS
CMPS
IGNITION
MODULE
IGNITION
MODULE
ECTS
VVT
VVT
KS
HO2S
HO2S
HO2S
EOTS
HO2S
A BANK
B BANK
CKPS
T880.05
2.6
Student Guide
Service Training
AJ27 N/A ENGINE MANAGEMENT INPUTS / OUTPUTS
FUEL PUMP
RADIATOR FANS
A/C COMPRESSOR
CLUTCH
FUEL PUMP
RELAY
RADIATOR
FAN CONTROL
RELAY MODULE
A/C COMP.
CLUTCH
RELAY
ECM SWITCHED POWER
BATTERY POWER
IGNITION SWITCHED
POWER
MAFS
BARO
FUEL INJECTOR
POWER SUPPLY
IATS
EMS
CONTROL
RELAY
BATTERY POWER
FUEL
INJECTION
RELAY
BATTERY POWER
IGNITION
COIL
RELAY
BATTERY POWER
ECM SWITCHED
POWER
ECTS
IGNITION
POWER SUPPLY
CKPS
ECM SWITCHED
POWER
CMPS (A)
ECM SWITCHED POWER
CMPS (B)
HO2S (A/1)
THROTTLE
MOTOR
POWER
RELAY
BATTERY POWER
HO2S (A/2)
HO2S (B/1)
A/C REFRIGERANT
4-WAY
PRESSURE
SWITCH
HO2S (B/2)
HO2S HEATERS
KS (A)
CPU 1
CRUISE
CONTROL
SWITCHES
KS (B)
PPS1
PPS2
BRAKE
SWITCH
THROTTLE MOTOR
TPS1
BRAKE
CANCEL
SWITCH
TPS2
FUEL INJECTORS
AAI
IGNITION MODULES
PARKING
BRAKE
SWITCH
CPU 2
VVT (A)
VVT (B)
INERTIA
SWITCH
EOTS
(CRASH SENSING /
THROTTLE MONITOR)
EVAPP
A/C COMPRESSOR CLUTCH REQUEST (A/CCM)
CCV
FTPS
SECURITY INTERFACE
EEPROM FLASH PROGRAMMING
DIAGNOSTIC
MONITORING
DATA
CAN (NETWORK):
• ABS/TCCM
• TCM
• INSTRUMENT PACK
T880.06
Student Guide
2.7
Service Training
CONTROL SUMMARIES
System Logic: AJ27 SC
AJ27 SC ENGINE MANAGEMENT SENSORS AND COMPONENTS
IATS
MAFS
PPS
TPS
THROTTLE
MOTOR
MAPS
EGR
FI
FI
IATS 2
IGNITION
MODULE
CMPS
ECTS
CMPS
IGNITION
MODULE
KS
HO2S
HO2S
A BANK
B BANK
HO2S
HO2S
CKPS
2.8
Student Guide
T880.07
Service Training
AJ27 SC ENGINE MANAGEMENT INPUTS / OUTPUTS
FUEL PUMP 1
FUEL PUMP 2
CHARGE AIR
COOLER PUMP
FUEL PUMP
1
RELAY
FUEL PUMP
2
RELAY
CHARGE AIR
COOLER
PUMP RELAY
RADIATOR
FANS
A/C
COMPRESSOR
CLUTCH
RADIATOR
FAN
CONTROL
RELAY MOD.
A/C COMP.
CLUTCH
RELAY
BATTERY POWER
ECM SWITCHED
POWER
EMS
CONTROL
RELAY
MAFS
BATTERY
POWER
IATS 2
ECTS
FUEL
INJECTOR
PWR SUPPLY
BARO
CKPS
FUEL
INJECTION
RELAY
BATTERY
POWER
ECM
SWITCHED
POWER
CMPS
IGNITION
PWR SUPPLY
CMPS
IGNITION
COIL
RELAY
HO2S
ECM SWITCHED
POWER
KS
IATS
THROTTLE
MOTOR
POWER
RELAY
BATTERY
POWER
ECM
SWITCHED
POWER
BATTERY
POWER
FTP SENSOR
A/C REFRIGERANT
4-WAY
PRESSURE
SWITCH
THROTTLE
CPU 1
CRUISE
CONTROL
SWITCHES
FUEL
INJECTORS
IGNITION
MODULES
BRAKE
SWITCH
HO2S
HEATERS
EVAPP
PARKING
BRAKE
SWITCH
CCV
EGR
MAPS
CPU 2
DIAGNOSTIC
MONITORING
SECURITY INTERFACE
DATA
CAN (NETWORK):
• ABS/TCCM
• TCM
• INSTRUMENT PACK
T880.08
Student Guide
2.9
2.10
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
AJ26 Engine Control Module
The two-microprocessor ECM is located in the engine
compartment right hand control module enclosure
(cool box).
AJ26 ENGINE CONTROL MODULE
All XK8 vehicles, and XJ8 Supercharged vehicles incorporate a cooling fan in the right hand control module
enclosure. The cooling fan is operated continuously while
the ECM is active from an ECM controlled power supply.
T880.09
Volatile memory Quiescent current from the vehicle
battery is used to keep the ECM random access memory (RAM) active so that OBD generated DTCs and
adaptive values are maintained. If the vehicle battery is
disconnected, the ECM will “relearn” adaptive values
during the next driving cycle.
The ECM has several adaptive learning functions, including:
• Closed loop fuel metering
• Closed loop throttle control
• Idle speed
• Long term fuel metering feedback correction
Nonvolatile memory A nonvolatile memory stores the vehicle identification number (VIN).
Barometric Pressure Sensing
A barometric pressure sensor (BARO) is incorporated into the ECM. The BARO input is used for fuel metering barometric pressure correction. In addition, certain diagnostic monitoring is inhibited at high elevation. The BARO
cannot be replaced separately.
ECM Default Action(s)
Most detected faults are accompanied by an ECM default action. In instances where the driver will notice a difference in vehicle performance and/or the vehicle requires fault correction, visual indication is displayed on the
instrument pack. The indicators include: the general warnings – RED and AMBER MILs, the CHECK ENGINE MIL,
and the message display. Specific ECM default action(s) are included with each DTC listed in the applicable DTC Summaries book section.
ECM Cooling
A fan is used to cool the ECM and the TCM. To prevent ECM overheating and subsequent degrading of performance, this fan, located in the control module enclosure, operates at all times when the ignition is switched ON and
circulates air from the passenger compartment through the “cool box”.
ECM Electrical Connection
The ECM connects to the engine management harness via six multi-pin connectors. The applicable Electrical Guide
shows the connector pin / wire color codes for the particular variant.
3.2
Student Guide
Service Training
AJ26 ECM CONNECTOR SOCKETS
EM14
EM15
6
5
4
3
2
1
11
12
11
10
9
8
7
22
EM14
EM15
16
9
7
15
26
34
8
14
25
33
6
24
32
23
4
3
2
1
12
21
31
20
8
7
19
6
18
20
30
19
29
11
18
28
6
11
17
5
10
17
27
22
4
2
21
14
16
3
15
EM12
1
8
15
4
14
2
1
13
12
EM11
EM10
EM11
3
9
16
5
17
EM12
5
13
22
21
9
EM13
EM13
10
10
13
20
4
7
1
6
11
18
EM10
2
7
12
19
3
16
10
15
9
14
8
5
13
8
13
7
28
5
12
21
12
6
4
3
2
11
20
27
19
26
18
1
10
17
16
25
15
24
9
14
23
22
T880.10
EMS Power Supplies
Engine management and transmission control module power supplies flow through the engine management fuse
box located in the engine compartment. The engine management power bus is controlled by the ECM via the EMS
control relay located in the fuse box. When the ignition is switched to position II, the ECM completes the relay coil
circuit to ground to power the bus. When the ignition is switched OFF, the ECM will continue to activate the EMS
control relay for a period of four seconds minimum to five minutes maximum. The power supplied during this period allows the ECM to complete diagnostics, perform closed throttle adaptions, close the EGR valve (if fitted), and
operate the radiator fans. Refer to the applicable Electrical Guide for relay and fuse box locations
AJ27 EMS POWER SUPPLIES
HIGH POWER
PROTECTION MODULE
250A
BATTERY
III
II
O
I
IGNITION
SWITCH
EMS CONTROL
RELAY
IGNITION POSITIVE
RELAY
B+
B
ENGINE
CONTROL MODULE
ENGINE COMPARTMENT
FUSE BOX
Student Guide
ENGINE MANAGEMENT POWER BUS
IGNITION POWER BUS
E
B+
BATTERY POWER BUS
B+
II
EMS BATTERY
POWER SUPPLIES
EMS ECM CONTROLLED
POWER SUPPLIES
ENGINE MANAGEMENT
FUSE BOX
T880.10A
3.3
Service Training
AJ26 Engine Control Module (continued)
ECM “Limiting” Control
The ECM performs “limiting” functions to achieve refinement, aid in vehicle control, and to protect certain components from damage. The table summarizes how the ECM implements “limiting” control.
Function
Throttle
ECM Intervention
Fuel Injection
Ignition
ECM Control
Engine overspeed protection
X
Engine speed limited to 7100 rpm.
Engine default speed
X
Engine speed limited to 3000 rpm.
Engine power limiting
X
Throttle valve opening limited to 18˚
maximum – when TCM detects a transmission
fault or when reverse gear is selected.
Vehicle speed limiting
X
Vehicle speed limited to 155 mph (248 km/h).
Traction / Stability control
X
Shift energy management
X
X
Engine torque momentarily reduced for
traction / stability control.
X
Engine torque momentarily reduced to
enhance transmission shift quality.
Engine overspeed protection
The ECM limits engine speed for overspeed protection by canceling fuel injection at 7100 rpm. Fuel injection is
reinstated at 7050 rpm. Ignition retard is used to “smooth” the transition between fuel injection on / off / on.
Engine default speed
When the ECM detects an EMS fault that warrants a reduction in the available engine speed range, it limits the maximum engine speed to 3000 rpm. Engine default speed is limited by fuel injection intervention.
Engine power limiting
Engine power is limited in two instances – transmission faults and reverse gear selection. If the TCM detects a fault
that requires engine torque reduction, it communicates with the ECM by the CAN message CAN TRANSMISSION
OVERLOAD. In response, the ECM limits engine power by limiting the throttle valve opening to 18° maximum in all
forward gears. Normal throttle operation is reinstated when the CAN message is no longer communicated by the TCM.
As REVERSE gear is selected, the TCM also communicates the CAN message CAN TRANSMISSION OVERLOAD and the
ECM limits engine power by limiting the throttle valve opening to 18° maximum. Normal throttle operation is reinstated when the transmission is shifted out of REVERSE and the CAN message is no longer communicated by the TCM.
NOTES
3.4
Student Guide
Service Training
Vehicle speed limiting
The maximum vehicle speed is limited to 155 mph (248 km/h) by throttle intervention. The ECM receives vehicle
speed data from the CAN message CAN VEHICLE SPEED, transmitted by the ABS/TCCM.
Traction / Stability control
The ABS/TCCM determines when engine torque reduction is necessary for traction control and/or stability control.
In addition, the ABS/TCCM determines what type of engine intervention should be applied, and the amount of
torque reduction required. This determination is made based on the CAN data provided by the ECM CAN message
CAN TRACTION CONTROL ESTIMATED ENGINE TORQUE. Three distinct ABS/TC CAN messages can be communicated by the ABS/TCCM:
• CAN TORQUE REDUCTION THROTTLE
• CAN FAST STABILITY CONTROL RESPONSE – CYLINDER FUEL CUTOFF
• CAN FAST STABILITY CONTROL RESPONSE – IGNITION RETARD.
In response, the ECM reduces engine torque by applying intervention to throttle, fuel injection, and/or ignition. Fuel
injection and ignition intervention are used to provide an instantaneous response and to smooth the transition to
throttle intervention. The ECM acknowledges that torque reduction is taking place by confirming with the CAN
message CAN TRACTION ACKNOWLEDGE.
Shift energy management
Transmission shift quality is enhanced by “shift energy management”. The ECM provides engine torque data by the
CAN message CAN SHIFT ENERGY MANAGEMENT ESTIMATED ENGINE TORQUE. The TCM determines the
amount of torque reduction required. As gear shifts occur, the TCM communicates the CAN message CAN
TORQUE REDUCTION REQUEST. The ECM responds by retarding the ignition to momentarily reduce torque.
NOTES
Student Guide
3.5
Service Training
AJ27 Engine Control Module
The AJ27 ECM incorporates two microprocessors (CPU)
with increased processing power and memory capacity
over the AJ26 module, and has expanded hardware to
accommodate the increase in the number of system
sensors and components.
AJ27 ENGINE CONTROL MODULE
Non-volatile memory OBD generated DTCs and
adaptive values are stored and maintained in non-volatile memory. All stored DTCs and the adaptive values will
be maintained if the vehicle battery is disconnected.
T880.11
The ECM has new and revised functions as compared to AJ26. These include:
• Revised failure management modes.
• “Black box, flight recorder” / Inertia switch monitor
• Revised traction and stability control
• “Cool box” fan control
• Revised air conditioning interface
• Revised throttle control and cruise control operation.
• Revised transmission interface
AJ27 Revised Failure Management Modes
The ECM controls four failure management modes: cruise control inhibit, limp-home mode, engine shutdown
mode, and power limiting mode. As with AJ26, driver warnings (CHECK ENGINE MIL, Red MIL, Amber MIL, Message) and DTCs accompany the initiation of these modes. Cruise control inhibit and engine shutdown mode remain
unchanged. Specific revised ECM default actions are included with each DTC in the applicable section(s) of the DTC
Summaries book.
Limp-home mode
In limp-home mode the full authority throttle is deactivated by the ECM. The throttle is then operated directly by
the cable from the accelerator pedal. When the throttle limp-home lever is against the closed stop, the ECM maintains an idle speed of less than 1500 rpm (no load, Neutral / Park) by fuel injection intervention. Cruise control is
inhibited.
Power limiting mode
When intake air flow cannot be controlled by the throttle (mechanical jam, large air leak), the ECM deactivates the
throttle as in limp-home. Engine power is controlled by the ECM via fuel cutoff to some of the fuel injectors, disabling those cylinders. The amount of cylinder disablement is determined by the ECM from driver demand (PPS)
and engine speed (CKPS).
NOTES
3.6
Student Guide
Service Training
AJ27 Air Conditioning Interface
The radiator fan control strategy is based on the air conditioning four-way pressure switch inputs. This control strategy is applied only while the engine is running.
AJ27 Transmission Interface
Engine power limiting due to transmission control module (TCM) input occurs only when one or more of the following conditions occur:
• the transmission is in Reverse
• the transmission overload message is present (CAN)
• a gear selector fault occurs
• the TCM is not present on the CAN network
If the TCM receives the engine oil over temperature message (CAN), the transmission will hold fourth gear.
“Black Box, Flight Recorder” / Inertia Switch Monitor
The ECM records 10 seconds of throttle operational data in a “rolling’ memory in the volatile battery backed RAM.
The data is continuously updated and stored during engine operation. In the event of the inertia switch being
tripped, an ignition switched ground is applied to ECM pin EM82-12. The ECM copies the last 10 seconds of recorded throttle data into nonvolatile EEPROM and DTC 1582 is flagged. The DTC is cleared using PDU.
“Cool box” Fan Control
On vehicles equipped with a “cool box” fan, the ECM operates the fan when the engine is running. Additionally, the
fan is operated after engine shutdown as required based on operating and “heat soak” conditions.
NOTES
Student Guide
3.7
Service Training
AJ27 Engine Control Module (continued)
ECM Electrical Connection
The ECM connects to the engine management harness via six multi-pin connectors. The applicable Electrical Guide
shows the connector pin / wire color codes for the particular variant.
AJ27 ECM CONNECTOR SOCKETS
EM80
EM81
EM82
EM83
EM84
EM85
EM80
9
8
7
21
20
19
31
30
29
9
8
7
19
18
17
28
27
26
6
18
5
17
16
28
27
EM81
4
15
3
2
1
7
6
5
14
13
12
11
10
16
15
14
26
25
24
23
22
24
23
22
EM83
4
13
EM82
3
2
1
6
5
4
3
2
10
9
8
7
15
14
13
12
11
10
9
8
12
11
21
20
19
18
17
17
16
EM85
EM84
6
5
4
3
2
1
7
6
16
15
14
13
12
11
10
15
14
25
24
23
22
21
20
22
21
1
5
4
3
2
1
5
4
13
12
11
10
9
8
12
11
20
19
18
17
16
10
9
3
2
1
8
7
6
T880.12
AJ26 and AJ27 ECM Service “Flash Programming”
The ECM EEPROM can be flash programmed in service using PDU via the data link connector (DLC). If such a service action is required, instructions are included in a Service Bulletin.
NOTES:
•
•
•
•
ECMs must not be switched from one vehicle to another because the VIN will be mismatched.
If an ECM has been replaced in service, the VIN will display as 999999.
If a replacement ECM has not been factory programmed, a message will be displayed on the driver message center.
The following originally equipped ECMs cannot be flash programmed in service:
– 1998 MY XK8 VIN 020733 – 031302
– 1998 MY XJ8
VIN 819772 – 853935
These vehicles require a new pre-programmed replacement ECM. Refer to Technical Service Bulletins.
Always check the VIN before carrying out ECM flash programming.
•
NOTES
3.8
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
Mass Air Flow Sensor (MAFS) – AJ26
•
MAFS – AJ26
•
•
•
The MAFS, located between the air cleaner and the
air intake duct, provides the ECM with an engine
load input signal.
The MAFS is a hot wire type that measures air flow
volume by the cooling effect of air passing over a
heated wire, altering the electrical resistance of the
wire.
The electrical resistance value is converted to an
analog output voltage supplied to the ECM as a
measure of air flow volume (engine load).
10% of the engine combustion air volume is routed
over the heated wire allowing unrestricted air flow
for 90% of the air.
T880.13
Intake Air Temperature Sensor (IATS) – AJ26
•
IATS (IN MAFS HOUSING) – AJ26
•
•
•
The IATS, located within the MAFS housing, provides the ECM with an intake air temperature signal.
The IATS is a negative temperature coefficient
(NTC) thermistor. Intake air temperature is determined by the ECM by a change in resistance within
the sensor.
The ECM applies 5 volts to the sensor and monitors the voltage drop through the thermistor.
The IATS is not serviceable separately from the
MAFS.
IATS Temperature / Resistance
T880.14
Intake air temperature
˚C
˚F
-20
0
20
40
60
80
100
-4
32
68
104
140
176
212
Resistance
(kΩ)
15
5.74
2.45
1.15
0.584
0.32
0.184
NOTES
4.2
Student Guide
Service Training
Mass Air Flow and Intake Air Temperature Sensors (MAFS and IATS) – AJ27
The AJ27 MAFS and IATS are combined in an integral,
plug-in unit, secured by two screws to the duct. Sensor
characteristics remain the same.
MAFS AND IATS – AJ27
INTAKE AIR
TEMPERATURE
SENSOR
NOTES
AIR FLOW
T880.15
Student Guide
4.3
Service Training
Engine Coolant Temperature Sensor (ECTS) – AJ26 and AJ27
•
ECTS LOCATION
•
•
•
The ECTS is located on the coolant outlet elbow
between the A and B bank cylinder heads.
The ECTS is a negative temperature coefficient
(NTC) thermistor.
The ECM applies 5 volts to the sensor and monitors the voltage drop through the thermistor.
Engine coolant temperature is determined by the
ECM by a change in resistance within the sensor.
ECTS Temperature / Resistance
Coolant temperature
˚C
˚F
-10
0
20
40
60
80
100
T880.16
ECTS WITH CROSS-SECTION
14
32
68
104
140
176
212
Resistance
(kΩ)
9.20
5.90
2.50
1.18
0.60
0.325
0.19
ECTS Temperature / Voltage
Coolant temperature
˚C
˚F
THERMISTOR
-10
0
20
40
60
80
100
14
32
68
104
140
176
212
Voltage
(V)
4.05
3.64
2.42
1.78
1.17
0.78
0.55
ELECTRICAL
CONNECTOR
T880.17
NOTES
4.4
Student Guide
Service Training
Crankshaft Position Sensor (CKPS) – AJ26
•
•
•
•
•
The CKPS, located at the rear of the engine bed plate, provides the ECM with pulsed signals for crankshaft position and engine speed.
The timing disc for the sensor is spot-welded to the front face of the transmission drive plate.
The timing disc has 34 spokes spaced at 10° intervals, with two spokes deleted.
The sensor is a variable reluctance device that provides a pulse to the ECM at 10° intervals.
The CKPS input pulse is used by the ECM for ignition timing and fuel injection timing. In addition, the missing
pulses (and the CMPS input) are used to identify cylinder 1A, compression stroke for starting synchronization.
CKPS TIMING DISC – AJ26
CKPS – AJ26
T880.19
T880.20
Crankshaft Position Sensor (CKPS) – AJ27
The AJ27 CKPS has a revised 36-tooth (minus one tooth) reluctor. The electrical connection to the CKPS is direct.
CKPS RELUCTOR – AJ27
CKPS – AJ27
T880.22
Student Guide
T880.23
4.5
Service Training
Camshaft Position Sensor (CMPS) – AJ26
•
The variable reluctance CMPS, located on the rear of the B bank cylinder head, provides the ECM with a
pulsed signal for cylinder 1A compression stroke identification (one pulse per two crankshaft revolutions).
The pulse is generated by the raised segment of the camshaft timing ring as it passes the sensor tip.
The CMPS input pulse is monitored along with the CKPS signal for synchronizing ignition timing and fuel injection timing with engine cycle position.
In addition, the CMPS signal is used for variable valve timing (VVT) diagnostic monitoring.
•
•
•
CMPS TIMING RING – AJ26
CMPS LOCATION – AJ26
T880.24
T880.25
Camshaft Position Sensor (CMPS) – AJ27
•
•
•
•
•
Both engine banks incorporate camshaft position sensors that sense the position of the intake camshafts.
The CMP sensors are inductive pulse generators.
The sensors have four-toothed reluctors mounted on the rear of both intake camshafts.
The four-tooth reluctors provide faster camshaft position identification, improving engine start-up speed.
ECM uses the CMP signals for cylinder identification to control starting, fuel injection sequential operation,
ignition timing, and variable valve timing operation and diagnostics.
CMPS (A BANK SHOWN)– AJ27
CMPS RELUCTOR – AJ27
T880.28
4.6
Student Guide
T880.29
Service Training
Engine Cycle Synchronization: CKPS and CMPS
The engine cycle sensor pulse traces illustrate the relationship between the CKPS and the CMPS.
CKPS / CMPS 720˚ CRANKSHAFT ENGINE CYCLE – AJ26
CRANKSHAFT ROTATION IN DEGREES
0˚
+
180˚
360˚
540˚
720˚
0V
CAMSHAFT POSITION SENSOR (CMPS) SIGNAL
–
+
0V
–
CRANKSHAFT POSITION SENSOR (CKPS) SIGNAL
ONE ENGINE CYCLE (720˚)
CYLINDER 1A
TDC COMPRESSION
CYLINDER 1A
TDC COMPRESSION
T880.27
Engine Start: CKPS / CMPS – AJ27
Faster engine firing on start-up is assisted by the four-toothed sensor rings on each camshaft. Each sensor ring provides 4 pulses per engine cycle (720˚) to the ECM, compared with 1 pulse from the AJ26 single-tooth sensor ring
fitted to B bank. The sensor teeth are asymmetrically positioned and produce a corresponding pulse pattern over
the engine cycle, which is compared with the crank sensor output (one missing pulse per revolution). This feature
enables the ECM to more quickly identify where the engine is positioned in the firing order and thus trigger ignition
and fueling to fire the correct cylinder.
In normal operation, the ECM uses the inputs from the crank sensor and the A bank cam sensor for cylinder identification and ignition/fuel synchronization. If the A bank sensor system fails, the ECM switches to the B bank inputs. If
the crank sensor system fails, the engine will start and run using the inputs from both cam position sensors.
NOTES
Student Guide
4.7
4.8
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
5.2
Student Guide
Service Training
Service Training
INDUCTION AIR THROTTLE CONTROL – AJ26
ECM Throttle Control
The electronic throttle allows the ECM to perform the following functions:
• Intake air flow control
• Idle speed control
• Cruise control
• Engine torque reduction requirements for traction / stability control
• Engine power limiting
• Vehicle speed limiting
• Throttle diagnostics
• Adopt default modes of operation
Electronic Throttle Assembly
Engine induction air is metered by the electronic throttle assembly in response to driver input and control by the
ECM. ECM throttle control allows several previously independent subsystems such as engine power limiting and
idle control to be incorporated as EMS functions.
THROTTLE ASSEMBLY – AJ26 N/A
T880.30
Student Guide
5.3
Service Training
Throttle Assembly Components Identification
The main components of the AJ26 throttle assembly include:
• Input shaft Receives driver inputs from the accelerator pedal via a conventional throttle cable.
• Pedal position sensor A twin-track sensor (potentiometers) provides redundant pedal position signals to
the ECM.
• Mechanical guard Device that prevents the throttle valve from opening beyond driver demand. The
mechanical guard allows the throttle to be operated mechanically in the case of electronic control failure.
• Mechanical guard sensor A single-track sensor provides a mechanical guard position signal to the ECM.
• Vacuum actuator Active (vacuum applied to diaphragm chamber) when cruise control is activated. Operates
the mechanical guard independently in cruise control mode.
• Throttle valve Conventional shaft/plate arrangement. Sprung toward open position. Mechanical guard lever
holds throttle plate in closed position.
• Thermostatic air valve Controls throttle valve bypass port during engine warm-up. Fully closes during
engine warm-up period.
• Throttle motor Driven by the ECM to operate the throttle valve only in the close direction.
• Throttle position sensor (TPS) Twin “hall-effect” sensor provides redundant throttle position signals to the
ECM.
• Springs Springs connected to the input shaft and mechanical guard provide force against the driver input and
provide the “feel” of an accelerator. Springs connected to the throttle motor drive gear and the throttle valve
provide force against the throttle closing.
The arrangement of the sensors on both “sides” of the throttle valve allows the ECM to have closed loop throttle control.
Thermostatic air valve operation
• Before engine start-up, the throttle valve is in the default closed position (sprung against mechanical guard
lever with throttle plate slightly open).
• At low engine temperature, the idle air opening at the throttle plate is insufficient to provide enough air flow
for the engine to start.
• The thermostatic air valve is a wax capsule-operated valve that provides throttle bypass air for starting.
• The bypass valve is fully open at approximately -30 °C (-22 °F) and progressively closes until it is fully closed at
40 °C (104 °F).
• Engine coolant flow through the throttle body provides the temperature source to operate the valve.
NOTES
5.4
Student Guide
Service Training
ELECTRONIC THROTTLE – AJ26
VACUUM
ACTUATOR
THROTTLE
SPRING
THROTTLE
MOTOR
VENT
THERMOSTATIC
AIR VALVE
MECHANICAL GUARD
SPRING
COOLANT
OUTLET
COOLANT
INLET
T880.31
SIMPLIFIED VIEW OF ELECTRONIC THROTTLE – AJ26
VACUUM
ACTUATOR
THROTTLE
POSITION SENSOR
THROTTLE
VALVE
SPRING
FORCE
MECHANICAL
GUARD
MECHANICAL
GUARD SENSOR
INPUT
SHAFT
THROTTLE MOTOR
DRIVE GEAR
THERMOSTATIC
AIR VALVE
SPRING FORCE
SPRING
FORCE
PEDAL
POSITION SENSOR
T880.32
Student Guide
5.5
Service Training
Throttle Sensors
The throttle assembly incorporates three sensors:
• A twin “hall-effect” throttle position sensor (TPS)
• A twin-track pedal position sensor (PPS)
• A single-track mechanical guard sensor
The input signals from the three sensors allow the ECM to control the throttle (closed loop), perform diagnostics,
perform adaptions, and adopt throttle default modes. The three sensors share common power supply reference
voltage, and reference ground circuits. The reference ground circuit is also shared with the ECTS and the IATS.
Throttle Position Sensor (TPS)
The throttle position sensor (TPS) is a twin “Hall effect” sensor, located at the throttle motor side of the throttle
assembly. The throttle valve shaft drives the sensor mechanism, which acts upon the two Hall effect elements to
provide the ECM with redundant TPS voltage signals. The voltage signals range from approximately 0.5 V at idle to
4.75 V at wide open throttle (WOT). PDU defines the redundant circuits as “1” and “2”. Circuit 1 is identified as TPS
pin 3; circuit 2 is identified as TPS pin 2. Refer to the applicable Electrical Guide.
Pedal Position Sensor
The pedal position sensor is a twin track potentiometer, located at the accelerator cable side of the throttle assembly. The throttle input shaft drives the potentiometer wipers to provide the ECM with redundant pedal position
voltage signals. The voltage signals range from approximately 0.5 V at closed to 4.75 V at full throttle. PDU defines
the redundant circuits as “A” and “B”. Circuit A is identified as pedal position sensor pin 5; circuit B is identified as
pedal position sensor pin 3. Refer to the applicable Electrical Guide.
Mechanical Guard Sensor
The mechanical guard sensor is a single track potentiometer, located at the accelerator cable side of the throttle
assembly. The mechanical guard shaft drives the potentiometer wiper to provide the ECM with a mechanical guard
position signal voltage. The signal voltage ranges from approximately 0.5 V at closed to 4.75 V at full open.
NOTES
5.6
Student Guide
Service Training
THROTTLE AND SENSORS – AJ26
PEDAL POSITION
SENSOR
MECHANICAL GUARD
SENSOR
THROTTLE POSITION
SENSOR
T880.33A
Student Guide
5.7
Service Training
Throttle Assembly Design Overview
•
•
•
The throttle assembly rotating components are arranged such that no fixed connection is made.
The input shaft moves the mechanical guard via a lever.
The throttle valve is restrained by the mechanical guard lever on one side and rotated by spring force on the
drive side.
The throttle motor segment gear rotates in one direction to allow throttle opening by spring force or motors in
the other direction to close the throttle against spring force.
•
THROTTLE LEVERS AND GAPS – AJ26
SPRING
FORCE
THROTTLE VALVE /
THROTTLE MOTOR
MECHANICAL GUARD /
THROTTLE VALVE
INPUT SHAFT /
MECHANICAL GUARD
SPRING FORCE
SPRING
FORCE
T880.33
•
The design of the input shaft and the mechanical guard, and the counter force applied by their respective
springs, ensures that they always rotate together when driver input is being applied from the accelerator pedal.
The accelerator rotates the input shaft and the mechanical guard in the open direction; the springs keep their
adjacent levers in contact and rotate them in the closed direction.
The motor acts only to close the throttle valve from the mechanical guard position.
The ECM controls engine idle speed by activating the motor closed to regulate an idle air way in the throttle
bore with throttle plate. This is achieved by closing the throttle plate past the default mechanical guard open
limit to the factory-set stop on the throttle motor segment gear.
•
•
•
NOTES
5.8
Student Guide
Service Training
Throttle Operation
Normal Mode
•
•
The ECM monitors the position of the input shaft and the mechanical guard using signals from the pedal position and mechanical guard sensors.
In response to the pedal position signal input, the ECM drives the throttle motor to follow the input shaft and
mechanical guard rotation to maintain a constant gap between the mechanical guard and throttle valve levers.
THROTTLE OPERATING MODES – AJ26
NORMAL MODE
SPRING
FORCE
SPRING FORCE OPENS THROTTLE;
THROTTLE MOTOR CLOSES THROTTLE
SPRING FORCE
SPRING
FORCE
T880.34A
•
•
•
•
The throttle motor drive gears rotate the throttle valve in the closed direction; the throttle valve spring turns
the throttle valve in the open direction while maintaining contact between the motor side throttle lever and
the segment gear.
The arrangement of the throttle valve drive prevents the ECM from exceeding driver demand. If the throttle is
driven open (without driver input to move the mechanical guard), the drive side throttle lever will disengage
from the segment gear, and the input side throttle lever will contact the mechanical guard lever preventing further throttle opening.
Since the mechanical guard restricts throttle movement only in the open direction, the arrangement of the
throttle valve also allows the ECM to reduce throttle opening to less than driver demand. Throttle opening is
reduced during traction control / stability control and during engine power limiting.
At idle, the ECM controls engine speed using the limited range of throttle valve movement available between
the mechanical guard (open limit) and the factory set stop on the throttle motor segment gear (closed limit).
NOTES
Student Guide
5.9
Service Training
Throttle Operation (continued)
Mechanical Guard Mode
•
•
If a throttle fault is detected, the ECM defaults to mechanical guard operating mode. In mechanical guard
mode, the throttle valve spring turns the throttle valve in the open direction until it engages the mechanical
guard, and the ECM does not drive the throttle motor.
The input shaft, mechanical guard and throttle valve are then effectively locked together by their springs, so
that the accelerator pedal is in direct control of the throttle via the throttle cable.
MECHANICAL GUARD MODE
SPRING
FORCE
THROTTLE SHAFT SPRING MAINTAINS
CONTACT BETWEEN THROTTLE SHAFT
AND MECHANICAL GUARD
SEGMENT GEAR MOVED;
NO MOTOR DRIVE
INPUT SHAFT DRIVES THROTTLE VALVE
VIA MECHANICAL GUARD
SPRING FORCE
SPRING
FORCE
T880.34B
•
•
•
•
When the throttle valve opens, it rotates the throttle motor drive gears. On subsequent closing of the throttle
valve, the segment gear remains in the open position, disengaged from the throttle valve.
Full throttle is available and engine speed is not limited in mechanical guard mode.
Fuel injection intervention smoothes the transition from normal mode to mechanical guard mode to prevent a
sudden increase in engine speed. In addition, fuel injection intervention limits idle speed by switching off
selected injectors.
Without fuel injection intervention, the idle speed would be approximately 2000 rpm and cause excessive
shock loads on the transmission when shifting out of P or N. As engine load increases, the ECM progressively
cancels idle fuel injection intervention.
NOTES
5.10
Student Guide
Service Training
Cruise Control Mode
•
•
When cruise control is engaged, the ECM calculates the required throttle valve angle and ports vacuum to the
vacuum actuator.
The vacuum actuator moves the mechanical guard to a position that allows the throttle motor to move the
throttle to the desired angle.
CRUISE CONTROL MODE
SPRING
FORCE
VACUUM ACTUATOR MOVES MECHANICAL
GUARD, ALLOWING THROTTLE MOTOR
TO POSITION THROTTLE VALVE
SPRING FORCE
SPRING
FORCE
T880.34C
•
•
•
Using the input signals from the throttle sensors, the ECM monitors and adjusts the mechanical guard and the
throttle valve to maintain the cruise control set speed.
As the driver releases the accelerator pedal, the input shaft disengages from the mechanical guard.
When accelerating above the set speed during cruise control, the accelerator pedal has a “lighter feel” until the
input shaft engages with the mechanical guard.
NOTES
Student Guide
5.11
Service Training
THROTTLE OPERATING MODES SUMMARY
SPRING
FORCE
NORMAL
SPRING FORCE OPENS THROTTLE;
THROTTLE MOTOR CLOSES THROTTLE
SPRING
FORCE
MECHANICAL GUARD
SPRING
FORCE
THROTTLE SHAFT SPRING
MAINTAINS CONTACT BETWEEN
THROTTLE SHAFT AND
MECHANICAL GUARD
SEGMENT GEAR MOVED;
NO MOTOR DRIVE
INPUT SHAFT DRIVES THROTTLE VALVE
VIA MECHANICAL GUARD
SPRING
FORCE
CRUISE CONTROL
SPRING
FORCE
VACUUM ACTUATOR MOVES MECHANICAL
GUARD, ALLOWING THROTTLE MOTOR
TO POSITION THROTTLE VALVE
SPRING
FORCE
5.12
T880.34D
Student Guide
Service Training
Cruise Control – AJ26
Cruise Control Vacuum Components
CRUISE CONTROL VACUUM COMPONENTS (XK8) – AJ26
Vacuum is supplied from the intake manifold and is
applied to the mechanical guard vacuum actuator on
the throttle assembly.
The vacuum components
include:
• One check valve
• Two vacuum reservoirs
• Three vacuum solenoid valves (VSV)
The vacuum components are installed in the right front
fender, behind the wheel arch liner.
Vacuum check valve
The check valve maintains vacuum in the system when
the throttle valve is in a position where little or no manifold vacuum is available (approximately 3/4 to full
throttle).
RESERVOIRS
VSV 2
CHECK
VALVE
VSV 1
VSV 3
T880.37
Vacuum reservoirs
If the throttle valve is positioned so that little or no manifold vacuum is available, the vacuum reservoirs can maintain system vacuum for up to 20 minutes. If the reservoirs are depleted of vacuum, normal system operation can be
restored by reducing vehicle speed for a short period of time.
VSV 1 (vacuum)
When cruise control is engaged, the ECM grounds the VSV 1 circuit and VSV 1 is driven to port vacuum to operate
the mechanical guard vacuum actuator.
VSV 2 (atmosphere)
The ECM grounds the VSV 2 circuit. VSV 2 is driven to port the operating vacuum to atmosphere until the mechanical guard is set to the required position. The ECM determines the required position via the mechanical guard
sensor. When cruise control is disengaged, the ECM grounds the VSV 2 circuit and VSV 2 is driven to port the operating vacuum to the atmosphere and release the mechanical guard vacuum actuator.
VSV 3 (release)
VSV 3 is driven by the ECM to act as a safety back up for VSV 2. The ECM switches the supply side of the VSV 3
circuit.
VSV Filters
VSV 2 and 3 incorporate filters to prevent moisture and debris from entering the system.
NOTES
Student Guide
5.13
Service Training
Cruise Control – AJ26 (continued)
Cruise Control Operation
•
CRUISE CONTROL MASTER SWITCH
•
•
•
•
T880.35
•
CRUISE CONTROL STEERING WHEEL SWITCHES
The driver communicates with the ECM through
the master switch in the center console and the
SET+, SET-, CANCEL, and RESUME switches on
the steering wheel.
The ECM also monitors two brake switch inputs and
the parking brake switch to cancel operation.
The cruise control system is powered when the
master switch is ON. Battery voltage is applied to
the ECM directly from the master switch and via
the normally closed brake cancel switch.
With the system powered, a momentary press of
either the SET+ or the SET- switch engages cruise
control if the vehicle speed is 17.5 mph (28 km/h)
or greater.
The ECM responds by “memorizing” the current
vehicle speed (CAN data) as the “set” speed.
The ECM drives the vacuum system to position the
mechanical guard so that the throttle can maintain
the set speed. The input signals from the pedal
position, mechanical guard and throttle sensors
allow the ECM to monitor and adjust the mechanical guard and the throttle valve.
NOTES
T880.36
5.14
Student Guide
Service Training
CRUISE CONTROL LOGIC – AJ26
B+
B+
CRUISE CONTROL
MASTER SWITCH
IGNITION SWITCH
VSV 2
BRAKE
SWITCH
BRAKE
CANCEL
SWITCH
B+
PEDAL POSITION AND
MECHANICAL GUARD
SENSORS
SET –
680 Ω
TPS
SET +
430 Ω
CRUISE
CONTROL
CONTROL
CANCEL
VSV 3
680 Ω
RES
430 Ω
MECHANICAL
GUARD
VACUUM
ACTUATOR
CRUISE CONTROL
STEERING WHEEL SWITCHES
M
THROTTLE
MOTOR
VSV 1
PARKING BRAKE SWITCH
CHECK VALVE
CKPS
CAN
• ABS/TCCM:
• TCM:
VEHICLE SPEED
OUTPUT SPEED
WHEEL SPEED
ACTUAL GEAR POSITION
TRACTION STATUS
TORQUE CONVERTER STATUS
GEAR POSITION SELECTED
RESERVOIRS
ECM
GEAR SELECTION FAULT
TRANSMISSION SHIFT MAP
T880.38
Student Guide
5.15
Service Training
Cruise Control – AJ26 (continued)
Cruise Control Operation
Acceleration / deceleration, change in set speed
• Once cruise control is engaged, a momentary press of the SET+ or SET- switches accelerates or decelerates the
vehicle speed incrementally by 1 mph (1.6 km/h).
• Pressing and holding the SET+ or SET- switches causes the ECM to smoothly accelerate or decelerate the vehicle until the switch is released.
• The ECM distinguishes the switched ground inputs by a difference in circuit resistance.
• The ECM stores a maximum of five SET+ / SET - incremental acceleration or deceleration commands at any
one time.
• Once the first stored command has been carried out, a further command can be added.
• If the opposite SET switch is pressed, the ECM deletes the last command from memory.
• After the vehicle is accelerated / decelerated incrementally, the ECM will adopt this speed as the set speed.
Accelerator pedal control
• Pressing the accelerator pedal will accelerate the vehicle higher than the set speed without disengaging cruise
control.
• Since the vacuum actuator holds the mechanical guard “open”, there is noticeably less accelerator pedal load
up to the point at which the throttle input shaft begins to move the mechanical guard.
CANCEL / RESUME
• A press of the CANCEL switch provides a cancel ground signal and the ECM smoothly disengages cruise control
and clears the set speed from memory.
• Pressing the RESUME switch provides a resume ground signal and the ECM reengages cruise control and
smoothly accelerates / decelerates the vehicle to the set speed.
Cruise control disengagement
The ECM disengages cruise control and clears the set speed from memory if any of the following conditions occur:
• The master switch is moved to OFF
• A fault is detected in the throttle assembly
• A fault is detected in the brake switch
• A fault is detected in the cruise control switches
• The parking brake is applied
• The engine speed exceeds 7100 rpm
The ECM disengages cruise control but retains the set speed in memory if any of the following conditions occur:
• The brake pedal is pressed
• The vehicle decelerates too fast (in case the brake switch is not operating)
• The gear selector is moved to P, N, R
• After resuming cruise control, the vehicle accelerates to only 50% of the set speed (due to a steep incline)
• Traction control / stability control operation
• Vehicle speed falls below 16 mph (26 km/h)
5.16
Student Guide
Service Training
CRUISE CONTROL LOGIC – AJ26
B+
B+
CRUISE CONTROL
MASTER SWITCH
IGNITION SWITCH
VSV 2
BRAKE
SWITCH
BRAKE
CANCEL
SWITCH
B+
PEDAL POSITION AND
MECHANICAL GUARD
SENSORS
SET –
680 Ω
TPS
SET +
430 Ω
CRUISE
CONTROL
CONTROL
CANCEL
VSV 3
680 Ω
RES
430 Ω
MECHANICAL
GUARD
VACUUM
ACTUATOR
CRUISE CONTROL
STEERING WHEEL SWITCHES
M
THROTTLE
MOTOR
VSV 1
PARKING BRAKE SWITCH
CHECK VALVE
CKPS
CAN
• ABS/TCCM:
• TCM:
VEHICLE SPEED
OUTPUT SPEED
WHEEL SPEED
ACTUAL GEAR POSITION
TRACTION STATUS
TORQUE CONVERTER STATUS
GEAR POSITION SELECTED
RESERVOIRS
ECM
GEAR SELECTION FAULT
TRANSMISSION SHIFT MAP
T880.38
Student Guide
5.17
Service Training
Full Authority Electronic Throttle Control
A full authority throttle body is fitted to the AJ27 engine. The throttle body does not incorporate a mechanical guard.
The main features of the AJ27 throttle body are:
• Full motorized control of the throttle valve from the ECM
• Mechanical, cable operated ‘limp home’ fail safe mode (restricted throttle opening)
• Mechanical, electrical and software safety features
• ECM cruise control drive (no vacuum components)
• Built-in air assist control valve (AACV) with integral air feed (normally aspirated only)
Throttle Components
THROTTLE BODY – AJ27 N/A
THROTTLE POSITION
SENSOR
THROTTLE MOTOR
COOLANT RETURN
COOLANT FEED
PEDAL POSITION
SENSOR
AIR ASSIST
OUTLET TO
FUEL INJECTORS
AIR ASSIST
CONTROL VALVE
T880.39
5.18
Student Guide
Service Training
THROTTLE BODY COMPONENTS – AJ27
THROTTLE POSITION
SENSOR
THROTTLE SHAFT
LEVER
PEDAL POSITION
SENSOR
ACCELERATOR LEVER
RETURN SPRING
INPUT SHAFT
LINK LEVER
INPUT SHAFT LINK LEVER
RETURN SPRING
LIMP HOME LEVER
LIMP HOME
SPRING
DRIVE MOTOR
AND GEARS
THROTTLE RETURN
SPRING
T880.43A
Input Assembly
The accelerator pedal is linked to the input shaft link lever of the throttle assembly. As the driver depresses the pedal, the link lever is rotated against spring pressure with no mechanical connection to the throttle valve.
PPS CHARACTERISTIC – AJ27
5V
PPS 1
VOLTAGE
PPS 2
0V
84°
(MAX DEMAND)
0°
DEMAND POSITION (DEGREE OF ROTATION)
Pedal position sensor (PPS)
• Two individual rotary potentiometers comprise the
PPS assembly located at the cable end of the throttle.
• The potentiometers are rotated by the throttle
cable lever and provide separate analog voltage
signals to the ECM proportional to pedal movement and position.
• The potentiometers have common reference voltage and reference ground circuits hard-wired to
the ECM.
• Each potentiometer provides its unique pedal position signal (via hard-wire connection) directly to
the ECM. The ECM detects faults by comparing the
pedal position signals to expected values.
• If the ECM detects a fault, throttle operation
defaults to the “limp home” mode (mechanical).
T880.41
Student Guide
5.19
Service Training
Throttle Components (continued)
Motorized Throttle Valve
•
The throttle valve is coupled to a DC motor via reduction gears and is positively driven by the ECM in both directions
between fully closed and fully open.
The throttle position sensor on the motor end of the throttle shaft provides direct feedback of the actual valve
angle to the ECM and is similar to the pedal position sensor in operation.
•
TPS CHARACTERISTIC – AJ27
5V
VOLTAGE
TPS 2
TPS 1
0V
Throttle position sensor (TPS)
• The throttle position sensor assembly consists of
two individual rotary potentiometers that are
directly driven by the throttle valve shaft.
• The potentiometers have common reference voltage and reference ground circuits hard-wired to
the ECM; each provides its unique throttle position
signal (via hard-wire connection) directly to the
ECM.
• The unique characteristics of both signals are used
for identification, similar to the PPS signals.
• The ECM detects faults by comparing the throttle
position signals to expected values. If the ECM
detects a fault, throttle operation defaults to the
“limp home” mode (mechanical).
84°
(WIDE-OPEN
THROTTLE)
0°
THROTTLE POSITION (DEGREE OF ROTATION)
T880.42
NOTES
5.20
Student Guide
Service Training
Throttle Operation
The throttle body contains two moving assemblies:
• the accelerator input assembly, which provides the driver demand to the ECM
• the motorized throttle valve, driven and controlled by the ECM in accordance with driver demand and other
EMS factors.
• In normal operation, there is no mechanical coupling between the two assemblies.
ECM THROTTLE CONTROL AND MONITORING – AJ27
INTAKE AIR
PEDAL
POSITION
SENSOR
THROTTLE
POSITION
SENSOR
M
ACCELERATOR
PEDAL
THROTTLE
MOTOR
THROTTLE MOTOR
DRIVE (+ / –)
PPS 1
TPS 1
PPS 2
TPS 2
CPU 2
THROTTLE MOTOR
POWER RELAY
B+ V
B+ V
THROTTLE MONITOR
SENSOR INPUTS
ENGINE SPEED / LOAD
DTC
CPU 1
T880.40
NOTES
Student Guide
5.21
Service Training
Limp Home Mechanism
•
•
•
•
•
The limp home mechanism consists of the accelerator input shaft link lever and the two throttle shaft levers, all
three levers being interlocked for limp home operation.
On the throttle assembly, one lever is fixed to the end of the shaft and the second, the ‘limp home’ lever, pivots around the shaft.
The two levers are connected by a spring and the throttle return spring is also connected to the limp home
lever.
As the throttle rotates, the action of the throttle lever (valve opening) and the springs (valve closing) maintain
the two levers in contact.
At the idle speed position, there is an angular separation between the accelerator link lever and the limp home
lever and under normal closed loop control this difference is maintained as both input and drive assemblies
rotate.
Limp Home Operation
If a failure in the throttle mechanism or control system occurs, the ECM defaults throttle control to the limp home mode.
• The ECM de-energizes the throttle motor power supply relay and / or deactivates the ECM internal PWM
motor drive signals.
• The throttle valve is operated mechanically from the drivers pedal and throttle opening is restricted to a range
from idle to a maximum of approximately 30°.
• The accelerator input shaft link lever is mechanically coupled to the throttle shaft levers, enabling the shaft to
be rotated against the unpowered motor and gearing.
• Due to the angular difference between the input shaft link lever and the limp home lever, there is no engagement of the two levers until the input shaft has rotated approximately 60° from idle.
• When the link lever contacts the limp home lever, causing it to rotate, the throttle valve is pulled open by the limp
home spring. With the pedal fully depressed the throttle valve is open to a maximum of approximately 30°.
• On releasing the accelerator pedal, the throttle return spring causes the limp home lever to rotate to its stop at
the throttle idle speed position.
• If loss of motor power occurs when the throttle is open beyond the idle position, the limp home lever will close
to the point where it contacts the link lever. If the throttle has been driven closed (past the idle position) when
loss of power occurs, the limp home spring will return the throttle to the idle position.
• When the throttle is in limp home mode, the ECM adjusts the fuel metering strategy as necessary to control
engine power. At low throttle opening, fuel cutoff to individual cylinders may occur.
NOTES
5.22
Student Guide
Service Training
THROTTLE OPERATION – AJ27
PART THROTTLE
LIMP HOME
T880.43B
NOTES
Student Guide
5.23
5.24
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
FUEL DELIVERY AND EVAPORATIVE EMISSION CONTROL
The fuel system uses a rear mounted over-axle fuel tank installed in the trunk. Fuel and vapor pipes travel under the
left hand side of the vehicle to the engine and evaporative emission components.
FUEL SYSTEM – AJ26 WITHOUT ENHANCED EVAPORATIVE EMISSION CONTROL
FUEL RAIL
FUEL PRESSURE
REGULATOR
EVAPORATIVE
FLANGE
EVAPORATIVE EMISSION
CONTROL VALVE
EVAPORATIVE
CANISTER
TANK PRESSURE
CONTROL VALVE
(ROCHESTER VALVE)
FUEL TANK
FUEL FILTER
T880.44
NOTES
6.2
Student Guide
FUEL TANK
JET
PUMP
CHECK
VALVE
Student Guide
VENT
EVAPORATIVE
CANISTER
PRESSURE
CONTROL VALVE
(ROCHESTER
VALVE)
FUEL PUMP
EVAPORATIVE
FLANGE
RESTRICTOR
SURGE
POT
ROLL-OVER
VALVE
FILTER
EVAPORATIVE
VALVE
(NORMALLY CLOSED)
FUEL
FLOW
PURGE
FLOW
PART LOAD
BREATHER
B BANK
FUEL
INJECTORS
ENGINE
CONTROL MODULE
PURGE
CONTROL
STRATEGY
INTAKE
MANIFOLD
FUEL RAIL
MANIFOLD
VACUUM
CONTROL
FUEL
PRESSURE
REGULATOR
A BANK
FUEL
INJECTORS
Service Training
FUEL DELIVERY AND EVAPORATIVE EMISSION CONTROL SYSTEM –
AJ26 WITHOUT ENHANCED EVAPORATIVE EMISSION CONTROL
T880.45
6.3
Service Training
Fuel Delivery
Fuel Tank
FUEL TANK ARRANGEMENT – XK8
SURGE POT
CHECK VALVE
TANK
•
•
•
•
JET PUMP
FUEL PUMP AND FILTER
BAFFLE PLATE
•
The fuel tank incorporates the fuel pump and the
necessary plumbing for fuel supply and return.
The pump is located by a rubber mount and clamp
attached to the surge pot.
The tank interior piping incorporates a jet pump
and a check valve in the fuel return line. Returning
fuel flows through the jet pump, which draws additional cool fuel from the tank to supply the surge
pot.
This supplemented return flow ensures that the
surge pot remains full of fuel. The return check
valve prevents reverse flow through the fuel return
line when it is disconnected.
Access to the tank interior is through the evaporative flange at the top of the tank.
T880.46
In-Line Fuel Filter
A replaceable in-line fuel filter is located in the supply
line to the front of the rear axle on the left side.
FUEL FILTER – XK8
Fuel Level Sensor
•
•
•
T880.47
•
The fuel level sensor is a conventional potentiometer that provides the instrument pack (INST) with a
variable voltage signal indicating fuel tank fill level.
The fill level signal voltage ranges between approximately B+ at empty to 0 V at full.
The INST transmits two fuel level CAN messages:
CAN FUEL LEVEL RAW – the raw (undamped) fuel
tank level, and CAN FUEL LEVEL DAMPED – the
damped (averaged over a period of time) fuel tank
level.
The INST provides the damped level message to
compensate for surges within the fuel tank.
NOTES
6.4
Student Guide
Fuel Pump
•
•
Service Training
FUEL PUMP WITH CROSS-SECTION
The single fuel pump unit consists of a turbine driven
by a DC motor, a check valve and an inlet filter.
The fuel output from the turbine pump provides a
cooling flow around the motor before being discharged through the outlet check valve. The check
valve prevents rapid fuel pressure loss when the
engine is switched off.
TOP VIEW
OUTLET
ELECTRICAL
CONNECTOR
Fuel pump specifications
Nominal pump delivery
26.45 gallons per hour at 3 bar (43.5 psi)
Current draw
7 amps at 13.2 V at 3 bar (43.5 psi)
Fuel pump operation
• The fuel pump is switched by the ECM via the fuel
pump relay.
• When the ignition is switched on (position II), the
ECM switches on the fuel pump after a delay of 0.1
second.
• If the ignition switch remains in position II without
moving the key to crank (position III), the ECM will
switch off the pump after a maximum of 2 seconds.
• When the ignition switch is moved to crank (position
III), the fuel pump is activated and operates continuously while the engine is running.
• If the engine stops with the ignition on (position II),
the ECM will switch OFF the pump after two seconds.
T880.48
NOTE: In the event of a vehicle impact, the inertia switch will switch off all ignition powered circuits,
including EMS power and fuel pump relay power. This action will switch off the fuel pump and prevent
fuel flow.
NOTES
Student Guide
6.5
Service Training
Fuel Delivery (continued)
Fuel Pressure Regulator
•
Fuel is pumped to the fuel rail and injectors, where fuel pressure is controlled by the fuel pressure regulator.
Excess fuel, above the engine requirement, is returned to the fuel tank through the fuel pressure regulator.
The pressure regulator spring chamber above the diaphragm is referenced to intake manifold vacuum.
The differential pressure across the fuel injector nozzles is therefore maintained constant and the quantity of
fuel injected for a given injector pulse duration is also constant.
Fuel pressure, measured on a test gauge, will vary between 2.7 bar (39 psi) at idle to 3.1 bar (45 psi) at full load
to compensate for intake manifold absolute pressure.
The fuel pressure regulator is located on the rear of the A bank fuel rail. This design provides the same pressure across each injector, and delivers an equal quantity of fuel to each of the eight cylinders.
Fuel flows through the B bank fuel rail, across the crossover pipe and through the A bank fuel rail. The fuel
rails are integral with the intake manifold.
The test valve, located in the crossover pipe allows the fuel rail to be de pressurized and pressurized during
testing and servicing. A standard fuel pressure gauge kit is used to connect to the test valve.
•
•
•
•
•
•
INTAKE MANIFOLD, FUEL RAILS AND FUEL PRESSURE REGULATOR – AJ26 N/A
FUEL INJECTOR
TEST VALVE
INTAKE MANIFOLD
PRESSURE
FUEL PRESSURE
REGULATOR
FUEL RETURN
T880.49
6.6
Student Guide
Fuel Injectors – AJ26
•
•
•
•
•
Service Training
FUEL INJECTOR CROSS-SECTION – AJ26 N/A
Eight solenoid operated fuel injectors are secured to
the fuel rail by cap screws.
The unique fuel injectors are side fed and have dual
straight jets.
The fuel spray from each jet is directed toward the
adjacent intake valve.
Two O rings seal each injector in the fuel rail bores.
B+ voltage is supplied to the injectors via the ignition
switch activated (position II, III) fuel injection relay.
The ECM drives the injectors with a single pulse
and modulates the pulse width to control the
injector pulse duration.
NOTES
RESISTANCE: 14.5 Ω @ 20˚C (68˚F)
T880.50
FUEL INJECTOR CHARACTERISTIC (TYPICAL)
INJECTOR PULSE: 2000 RPM, NO LOAD (REFERENCED TO GROUND)
40
VOLTAGE
30
20
10
0
10
0
MS
2
4
6
8
10
T880.51
Student Guide
6.7
Service Training
Evaporative Emission Control System – 1997 MY
The fuel tank can be filled to approximately 90% of its capacity. The additional 10% of volume allows for expansion
of the fuel, without escape to the atmosphere.
To limit evaporative emissions when the engine is switched off, the fuel tank pressure is maintained at a positive
pressure of 0.069 – 0.092 bar (1.0 – 1.33 psi) by the tank pressure control valve (Rochester valve). Pressure above
0.092 bar (1.33 psi) is released by the valve to the charcoal canister.
When the engine is running, manifold vacuum acts on the tank pressure control valve, which opens the vent line
from the fuel tank to the charcoal canister. Air enters the charcoal canister and flows to the tank to replace the fuel
delivered to the engine, and maintain atmospheric pressure in the tank.
If the tank pressure control valve fails, the fuel tank cap will vent the fuel tank to the atmosphere at 0.138 – 0.172 bar
(2.0 – 2.5 psi).
EVAPORATIVE EMISSION CONTROL SYSTEM
ROLL-OVER
VALVE
EVAPORATIVE
FLANGE
PART LOAD
BREATHER
FUEL TANK
INTAKE
MANIFOLD
MANIFOLD
VACUUM
CONTROL
VAPOR
FLOW
RESTRICTOR
PURGE
FLOW
PRESSURE
CONTROL VALVE
(ROCHESTER
VALVE)
PURGE
FLOW
EVAPORATIVE VALVE
(NORMALLY CLOSED)
PURGE
CONTROL
STRATEGY
VENT
EVAPORATIVE
CANISTER
ENGINE
CONTROL MODULE
T880.52
6.8
Student Guide
ECM Canister Purge Control
•
•
•
Service Training
EVAPORATIVE CANISTER ASSEMBLY
When the ECM enables canister purge, air flows in
the vent and through the charcoal canister to the
intake manifold via the normally closed evaporative
emission control valve (EVAPP) (purge valve).
The ECM drives the EVAPP to control purge using a
variable pulsed duty cycle from a mapped strategy.
The purge flow rate is based on engine operating
conditions and the concentration of fuel vapor in
the charcoal canister.
Engine operating conditions
The engine operating conditions that determine the
rate of canister purge are:
• Engine load and speed
• Coolant temperature
• Time since engine starting
• Closed loop fuel metering correction
TANK PRESSURE
CONTROL VALVE
During canister purge, the ECM inhibits traction / stability fuel injection intervention and fuel injection cutoff.
Determination of fuel vapor concentration
• The ECM determines the concentration of fuel vapor
being drawn from the charcoal canister and makes a
correction to the base fuel metering map.
• The determination is made by the ECM making step
changes to the purge flow rate while no correction is
made to the fuel metering calculation.
• The ECM determines the fuel vapor concentration
by analysis of the closed loop fuel metering deflection.
CANISTER
T880.53
EVAPORATIVE EMISSION CONTROL VALVE (EVAPP)
Evaporative Emission Control Valve (EVAPP)
•
•
•
•
The EVAPP is a vacuum operated, normally closed
purge valve.
T880.54
The EVAPP incorporates a vacuum switching valve
(VSV) that is supplied with EMS switched B+ voltage.
The ECM drives the VSV portion of the EVAPP (ground side switching), which ports manifold vacuum to a diaphragm and opens the valve to allow purge flow to the intake manifold.
The valve opening is modulated by the ECM from an operating strategy to control purge flow.
Student Guide
6.9
Service Training
Enhanced Evaporative Emission Control System – 1998 MY ON
1998 MY ON vehicles are equipped with a twin canister enhanced evaporative emission system that provides
reduced evaporative emissions and enhances the system’s on-board diagnostic capabilities.
The enhanced evaporative emission system consists of the following components:
• Fuel tank pressure sensor (FTP Sensor)
• Fill level vent valve
• Two evaporative canisters
• Canister close valve (CCV) and filter
• Evaporative emission valve (EVAPP)
Enhanced Evaporative Emission Control System Operation
When the engine is switched off, the fill level vent valve and/or the roll-over valve ports fuel tank vapors through the
vent line to the two carbon canisters. To maintain atmospheric pressure in the tank, air enters the canisters through
a filter via the normally open canister close valve.
When the engine is running and canister purge is enabled, the ECM meters purge flow from the canisters and tank
via the evaporative emission control (purge) valve (EVAPP). The ECM enables canister purge using a mapped
strategy.
NOTES
6.10
Student Guide
VENT
FILTER
FUEL TANK
SURGE
POT
ROLL-OVER
VALVE
CANISTER
CLOSE
VALVE
CHECK
VALVE
EVAPORATIVE
CANISTERS
JET
PUMP
FILL LEVEL VENT
VALVE
FUEL TANK PRESSURE
SENSOR
FUEL PUMP FUEL PUMP
1
2
(SC ONLY)
EVAPORATIVE
FLANGE
FILTER
FUEL
FLOW
CHECK
VALVE
PURGE
FLOW
Student Guide
MANIFOLD
VACUUM
CONTROL
FUEL
PRESSURE
REGULATOR
A BANK
FUEL
INJECTORS
ENGINE
CONTROL MODULE
OBD II
LEAK
CHECK
PURGE
CONTROL
STRATEGY
INTAKE
MANIFOLD /
SUPERCHARGER
FUEL TANK PRESSURE
EVAPORATIVE
VALVE
(NORMALLY CLOSED)
PART LOAD
BREATHER
B BANK
FUEL
INJECTORS
FUEL RAIL
Service Training
FUEL DELIVERY AND ENHANCED EVAPORATIVE EMISSION CONTROL SYSTEM – AJ26
T880.55
6.11
Service Training
Enhanced Evaporative Emission Control System – 1998 MY ON (continued)
Fuel Tank Pressure Sensor (FTP Sensor)
FUEL TANK PRESSURE SENSOR
•
•
The FTP sensor, located on the fuel tank evaporative flange, incorporates a pressure sensor capsule
connected to a resistive element.
The ECM supplies 5 volts to the resistive element,
which outputs a voltage signal proportional to the
fuel tank pressure.
Canister Close Valve (CCV)
•
•
The normally open CCV, located on the second
evaporative canister outlet, is operated by the ECM
from the purge control / leak check strategy.
A filter is installed on the vent hose to prevent
debris from entering the canister.
T880.56
NOTES
CANISTER CLOSE VALVE AND FILTER – XJ8 SEDAN
T880.57
6.12
Student Guide
Service Training
On-Board Refueling Vapor Recovery (ORVR)
•
•
•
•
•
•
•
•
•
ORVR, common to all 1998 MY ON vehicles, prevents the fuel tank vapor from being vented directly
to the atmosphere during refueling.
During refueling, vapor is vented through the EVAP
system.
The ORVR system consists of a unique fuel tank filler
neck incorporating a check valve, unique vent lines
and a fill level vent valve.
The lower part of the filler neck has a reduced diameter.
During refueling, the incoming fuel seals the gap
between the reduced part of the filler neck and the
refueling filler nozzle to prevent vapor from escaping
up the filler neck.
The check valve, located at the neck outlet to the
tank, prevents fuel from backing-up in the filler neck.
The fill level vent valve, located in the fuel tank evaporative flange, incorporates a float valve and a pressure relief valve.
The valve sets the maximum fuel level in the tank and
provides outlets to the EVAP system and to the filler
neck.
The roll-over valve also vents to the EVAP system.
Note that the vapor inlet to the roll-over valve is
located higher in the fuel tank than is the inlet to
the fill level vent valve.
ORVR FUEL TANK – XJ8 SEDAN
T880.58
FUEL TANK EVAPORATIVE FLANGE
ROLLOVER VALVE
FUEL TANK
PRESSURE SENSOR
FUEL PUMP
CONNECTOR
NOTES
FILL LEVEL VENT VALVE
T880.59
Student Guide
6.13
Service Training
On-Board Refueling Vapor Recovery (ORVR) (continued)
ORVR Operation
•
•
•
•
During refueling, the incoming fuel pushes fuel vapor through the roll-over valve and the fill level vent valve to
the EVAP system.
When the fuel level rises to close the float valve, ventilation is restricted causing a back pressure in the filler
neck sufficient to operate the refueling filler nozzle automatic shut-off.
After installing the filler cap, the fuel tank vents only through the roll-over valve until the fuel level drops to a
level that allows the float valve to open the fill level vent valve.
If the EVAP system fails so that the fuel tank cannot vent correctly, the fill level vent valve pressure relief valve
opens to allow vapor flow to the atmosphere through the filler neck and cap.
ORVR SYSTEM
CANISTER CLOSE
VALVE
ECM
CHARCOAL CANISTERS
FILTER
EVAP VALVE
FUEL TANK
PRESSURE SENSOR
FLOAT VALVE
INDUCTION
ELBOW
FUEL TANK
P
PRESSURE RELIEF
VALVE
FILLER CAP
CHECK VALVE
ROLLOVER VALVE
FILL LEVEL VENT VALVE
T880.60
NOTES
6.14
Student Guide
Service Training
On-Board Refueling Vapor Recovery (ORVR) – XK8
•
•
•
•
•
The XK8 enhanced evaporative emission system with ORVR is similar to the system used on the XJ8 Sedan.
Due to the large bore hoses required, the EVAP canisters and associated components are relocated to the rear
of the vehicle behind the rear suspension/final drive assembly.
The canister close valve (CCV) and vapor hoses are fixed directly to the bodywork.
The EVAP canisters are bolted directly and via brackets to the body.
The atmospheric vent pipe from the second canister is routed through a hole in the RH suspension housing
with the CCV air filter fitted to the end of the pipe inside the housing.
EVAP CANISTER INSTALLATION – XK8
VAPOR PIPE TO
PURGE VALVE
CCV FILTER
VAPOR FEED
FROM TANK
CANISTER
CLOSE VALVE
CANISTER
FIXING BOLT
CANISTER
MOUNTING BRACKET
T880.61
NOTES
Student Guide
6.15
Service Training
On-Board Refueling Vapor Recovery (ORVR) – XK8 (continued)
Fuel Tank Filler
Due to the relocation of the EVAP canisters, the vapor pipes pass through the floor of the trunk. Note that, on the
convertible model, the closing panel behind the tank is modified to accommodate the vapor pipes.
FUEL TANK – XK8
FUEL FILLER
TUBE SUPPORT
FUEL TANK OVER-PRESSURE
RELIEF PIPE
VAPOR OUTLET PIPE
TO CANISTERS
NARROW
FILLER TUBE
FUEL TANK
GROUND
CANISTER OUTLET PIPE
TO PURGE VALVE
T880.62
NOTES
6.16
Student Guide
Service Training
Crankcase Ventilation System
•
•
•
•
•
The engine crankcase is ventilated through a part
load and a full load breather.
Each camshaft cover incorporates a wire gauze air /
oil separator.
The part load breather connects between the B bank
air / oil separator and the intake manifold induction
elbow, and tees to the canister purge line.
The full load breather connects between the A bank
air / oil separator and the intake air duct, downstream from the MAFS.
AIR / OIL SEPARATOR
The breather hoses have quick release fittings.
NOTES
T880.63
CRANKCASE VENTILATION SYSTEM
PART LOAD BREATHER
FULL LOAD BREATHER
T880.64
Student Guide
6.17
6.18
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
FUEL INJECTION
Fuel Metering
Fuel metering is controlled by the ECM using a base fuel metering map, which is then corrected for the specific
engine operating conditions. The ECM varies the fuel injector pulse duration and the number of pulses during each
engine cycle (two crankshaft rotations) to achieve the necessary fuel metering. The injectors are pulsed sequentially, once per engine cycle (once every two engine revolutions) in the engine firing order, except during starting and
acceleration.
FUEL METERING STRATEGY
ENGINE LOAD
ENGINE SPEED
FUEL METERING
BASE MAP
PRIMARY INJECTOR
PULSE DURATION
CLOSED
LOOP
AIR : FUEL
RATIO
EXHAUST OXYGEN CONTENT
ENABLE / INHIBIT
ENGINE TRANSIENTS
CANISTER PURGE
CORRECTION
FACTORS
ENGINE START
STRATEGY
ENGINE CRANKING
AFTER-START
ENRICHMENT
ENGINE COOLANT TEMPERATURE
FULL LOAD
OVERRUN
VEHICLE ELEVATION
BATTERY
VOLTAGE
CORRECTION
BATTERY
VOLTAGE
INJECTOR
PULSE DURATION
ENGINE OPERATING CONDITION
CRANKSHAFT POSITION SENSOR
SEQUENTIAL
OR GROUPED
FUEL INJECTION
CAMSHAFT POSITION SENSOR
A BANK
B BANK
FUEL INJECTORS
T880.65
7.2
Student Guide
Service Training
Base Fuel Metering Map
•
•
•
•
•
The base fuel metering map sets the base air : fuel ratio for normal engine operation throughout the full range
of engine load and speed.
Engine load is determined by measuring intake mass air flow.
The MAFS supplies the ECM with a mass air flow signal.
The ECM receives an engine speed signal from the CKPS.
By monitoring the exhaust oxygen content from the HO2S (upstream oxygen sensors), the ECM is able to perform closed loop fuel metering control and adaptive fuel metering.
Closed Loop Fuel Metering
•
•
•
•
The exhaust system incorporates 3-way catalytic converters that oxidize CO and HC, and reduce NOx. These
converters operate efficiently only if engine combustion is as complete as possible.
A closed loop system between fuel injection, ECM control, and exhaust oxygen content feedback maintains an
air : fuel ratio as close to stoichiometric as possible.
In response to oxygen sensor voltage swings, the ECM continuously drives the air : fuel ratio rich-lean-rich by
adding to, or subtracting from the base fuel metering map.
Separate channels within the ECM allow independent control of A and B bank injectors.
Adaptive Fuel Metering
•
•
•
•
•
•
•
•
The ECM adapts fuel metering to variations in engine efficiency, subsystem tolerances, and changes caused by
engine aging.
Adaptions take place at normal operating temperature during engine idle, and at four other points within the
engine load / speed range.
While monitoring the HO2S feedback, the ECM centralizes fuel metering within the feedback range.
These adaptions can be measured by the PDU Datalogger Long Term Fueling Trim (LTFT) parameter.
The ECM retains the adaptions in memory, for use in subsequent drive cycles.
During the next drive cycle, the ECM monitors the adaptions taking place and compares them to the adaptions
that took place during the previous drive cycle for diagnostic purposes.
If the ECM battery power supply is disconnected, all adaptions will be lost from memory.
After reconnecting the battery power supply and starting the engine, engine operation may be uneven (especially at idle) until the ECM relearns the adaptions.
NOTES
Student Guide
7.3
Service Training
FUEL INJECTION
Fuel Metering (continued)
Engine Starting
The engine start strategy is used when the ECM receives an ENGINE CRANK signal from the BPM. With the exception of wide open throttle (WOT), the engine start strategy operates independently of accelerator pedal position or
movement. The engine start strategy initially increases injector pulse width to provide sufficient fuel for starting and
progressively reduces the pulse width during the cranking cycle. During the first 360° of crankshaft rotation, all fuel
injectors operate simultaneously. During subsequent revolutions the injectors are operated in the engine firing
order, once per 360° of crankshaft rotation. At engine speeds above 400 rpm the injectors operate normally. The
starting strategy produces steady-state running at the target idle speed within two seconds of firing after a maximum
overshoot of 200 – 300 rpm. If the accelerator pedal demands WOT during cranking, the ECM cancels fuel injection and allows the throttle valve to full open to clear the fuel vapor from the “flooded” engine intake.
Warm-Up Enrichment
During engine warm-up, the ECM controls fuel metering from maps that add an enrichment factor based on coolant
temperature, engine load and speed.
Transient Fuel Metering
During acceleration and deceleration, the ECM controls fuel metering to optimize the air : fuel ratio for exhaust
emission, engine response, and economy. This function operates over the full engine temperature range for all rates
of acceleration and deceleration.
NOTES
7.4
Student Guide
Service Training
Full Load Enrichment
The ECM determines full load from the throttle valve angle and the engine speed. At full load, the ECM inhibits
closed loop fuel metering control and increases fuel flow to enrich the air : fuel ratio. The amount of enrichment is
determined from the engine speed.
Evaporative Canister Purge Flow
During evaporative canister purge flow to the engine, the ECM determines the concentration of fuel vapor being
drawn from the evaporative canister and makes a correction to the base fuel metering map.
Overrun Fuel Injection Cutoff
When the throttle is closed during higher engine speeds, the ECM cancels fuel injection. The engine speeds at which
fuel injection is canceled and reinstated are mapped against coolant temperature. On reinstatement, the ECM initially uses a lean air : fuel ratio to provide a smooth transition, then progressively returns to the nominal air : fuel
ratio. The nominal air : fuel ratio for reinstatement is derived from throttle valve angle and engine speed. During
overrun fuel injection cutoff, closed loop fuel metering control, EVAP and EGR are inhibited.
Engine Overspeed Protection
To protect the engine from overspeed damage, the ECM cancels fuel injection at 7100 rpm. Fuel injection is reinstated at 7050 rpm.
Traction / Stability Control
Fuel injection intervention is used for traction / stability control.
NOTES
Student Guide
7.5
Service Training
FUEL INJECTION
Exhaust Gas Oxygen Content Monitoring: Oxygen Sensors – AJ26
•
OXYGEN SENSORS – AJ26
•
HO2S
•
•
•
•
O2S
•
•
T880.66
•
HEATED OXYGEN SENSOR WITH CROSS-SECTION – AJ26
•
The AJ26 EMS uses four zirconium dioxide type
oxygen sensors.
A heated oxygen sensor (HO2S) is located
upstream of each catalytic converter; an unheated
oxygen sensor (O2S) is located downstream of
each catalytic converter.
The two upstream sensors are used by the ECM for
closed loop fuel metering correction. The downstream sensors for used for OBD catalyst monitoring.
The oxygen sensors produce voltage by conducting
oxygen ions at temperatures above 300 °C (572 °F).
The tip portion of the sensor’s ceramic element is
in contact with the exhaust gas.
The remaining portion of the ceramic element is in
contact with ambient air via a filter through the
sensor body.
In order to reduce the time and resulting emission
needed to bring the upstream sensors up to working temperature, an internal electric heater is used.
The heaters are controlled by the ECM.
At engine speeds above approximately 3000 rpm,
the ECM switches off the heaters.
The construction of the upstream and downstream
sensor harnesses and connectors are different so
that they can be easily identified and not be interchanged.
The HO2S have a four-way connector; the O2S
have a two-way connector.
NOTES
PROTECTIVE TUBE
HEATER
ZiO2 – CERAMIC SENSOR TIP
7.6
T880.67
Student Guide
Service Training
OXYGEN SENSOR CHARACTERISTIC – AJ26
•
•
•
The sensor voltage varies between approximately
800 millivolts and 200 millivolts, depending on the
oxygen level in the exhaust gas.
When the air : fuel ratio is richer than optimum,
there is low oxygen in the exhaust gas and the voltage
output is high.
When the air : fuel ratio is leaner than optimum, oxygen in the exhaust is high and the output voltage is
low.
Only a very small change in air : fuel ratio is
required to swing the oxygen sensor voltage from
one extreme to the other, thus enabling precise
fuel metering control.
Catalytic Converters – AJ26
200mV
RICHER
λ = 1
(OPTIMUM)
LEANER
T880.68
OXYGEN SENSOR VOLTAGE SWING TRACE – UPSTREAM AJ26
The AJ26 engine exhaust system uses a single catalytic
converter for each engine bank. The placement of the
catalysts in the down pipes, adjacent to the exhaust
manifolds, ensures rapid “light off” and eliminates the
need for secondary catalysts.
Deterioration of catalytic conversion efficiency will create unacceptable HC, CO and NOx exhaust emission.
The efficiency of the catalytic converter system is monitored and any deterioration in efficiency is flagged as a
fault by the ECM. Catalyst efficiency is monitored by
sampling both the incoming and outgoing exhaust gas
at the catalysts. Two oxygen sensors are positioned in
each exhaust downpipe assembly – one HO2S
upstream of the catalyst and one O2S downstream of
the catalyst. By comparing the voltage swings of each
set of sensors, the ECM can detect when catalyst efficiency drops off.
0.86V
UPSTREAM OXYGEN SENSOR
•
OUTPUT VOLTAGE
800mV
Oxygen Sensor Characteristic
700mV
200mV
0V
10 SWINGS PER MINUTE AT IDLE
T880.69
CATALYTIC CONVERTERS – AJ26
NOTES
T880.70
Student Guide
7.7
Service Training
FUEL INJECTION
Oxygen Sensors – AJ27
“Universal” Oxygen Sensors
OXYGEN SENSOR CHARACTERISTIC – AJ27
•
APPLIED CURRENT
(APPROXIMATE)
+10 mA
•
NOMINAL APPLIED CURRENT
•
•
-10 mA
•
AFR 12:1
λ=1
AFR 18:1
UNIVERSAL OXYGEN SENSOR (UPSTREAM)
•
•
V
•
4.5V
In order to improve air : fuel ratio (AFR) control
under varying engine conditions, a “universal” type
heated oxygen sensor is fitted in the upstream
position.
The universal sensor has varying current response
to changes in exhaust gas content.
The AFR can be maintained more precisely within
a range from approximately 12:1 to 18:1, not just
stoichiometric.
Voltage is maintained at approximately 450 mV by
applying a current.
The current required to maintain the constant voltage is directly proportional to the AFR.
A higher current indicates a leaner condition; a
lower current indicates a richer condition.
The current varies with the temperature of the sensor and is therefore difficult to measure for technician diagnostic purposes.
The downstream heated oxygen sensors, used for
catalyst efficiency monitoring, remain unchanged.
However, the location in the exhaust system has
changed. Refer to the following page.
HO2S Heater Control
•
λ=1
OXYGEN SENSOR (DOWNSTREAM)
•
T880.75
The universal oxygen sensors require precise
heater control to ensure accuracy and prevent sensor damage.
After engine start, the ECM initially applies B+
voltage to the heaters to quickly warm the sensors,
then reduces the voltage as necessary to maintain
sensor temperature. The ECM varies the voltage
by PWM control of the individual heater ground
side circuits.
NOTES
7.8
Student Guide
Catalytic Converters – AJ27
Service Training
SPLIT ELEMENT CATALYTIC CONVERTER
Split Element Catalytic Converter
The AJ27 EMS produces very low levels on exhaust
emission. In order to allow detection of catalytic converter deterioration at these very low levels, a split
element catalytic converter is used.
To improve catalyst efficiency monitoring, the spacing
between the two internal ceramic catalytic elements
has been increased to allow the downstream HO2 sensor to be relocated to the new position between the two
elements. Due to the lower efficiency of the first (top)
element compared to the second element, the level of
exhaust emission at this location is sufficiently high to
ensure accurate monitoring.
UPSTREAM UNIVERSAL
HO2 SENSOR
DOWNSTREAM
HO2 SENSOR
T880.76
NOTES
Student Guide
7.9
Service Training
FUEL INJECTION
Air Assisted Fuel Injection – AJ27
Air assisted fuel injection (AAI) improves combustion stability when the engine is cold, allowing the use of increased
ignition retardation for faster catalyst warm-up, thus producing a further reduction of HC emission.
Under cold start/part throttle conditions, the system uses intake manifold vacuum to draw air through a modified
injector nozzle, producing a jet which mixes with the fuel spray to increase atomization. At higher engine loads, the
manifold vacuum is insufficient to have this effect. The injector air assistance supply is controlled by the ECM.
Injector Fuel and Air Supply
AAI INTAKE MANIFOLD – AJ27
•
•
•
•
FUEL RAIL
AIR SUPPLY RAIL
T880.71
Operation is based on the use of top (fuel) fed
injectors with an air feed around the nozzle
regions and therefore requires a modified induction manifold.
The injectors are seated in two air supply rails
which are integral with the manifold (similar to the
AJ26 fuel rails).
The rails are closed at both ends and are center fed
via plastic hoses and ‘T’ piece from the air assist
control valve (AACV).
Two fuel rails, with a connecting crossover pipe,
form a detachable assembly and are a push fit onto
the injectors to which they are secured with clips.
The fuel rails are then bolted to the induction manifold.
NOTES
FUEL RAIL AND INJECTORS – AJ27
FUEL RAIL
INJECTORS
T880.72
7.10
Student Guide
Fuel Injectors
•
•
•
Service Training
AAI FUEL INJECTOR CROSS-SECTION – AJ27
The injectors incorporate a shroud fitted over the
nozzle end to direct the AAI air flow.
Air from the supply rail is drawn by manifold vacuum
through four small holes in the side of the shroud and
past the fuel nozzle to exit via the two spray orifices in
the shroud.
When fuel is injected into this airflow, an
improved spray mixture with reduced droplet size
is produced.
FUEL SUPPLY
CONNECTOR
Air Assist Control Valve (AACV)
•
•
•
•
•
•
The air supply to the injectors is controlled by the
solenoid operated air assist control valve (AACV),
which is bolted to the throttle body.
The control valve receives air, via an integral passage
in the throttle body, from an entry hole in the upper
throttle bore above the throttle valve.
The ECM drives the AACV by a pulse width modulated (PWM) signal.
The valve opens in direct proportion to an increase in
the duty cycle.
The valve is fully open from cold until a coolant temperature of 60°C (140 °F).
Above 60°C (140 °F) a 50% duty cycle is applied
until 70 °C (158 °F), at which point the valve is fully
closed.
SHROUD
AIR SUPPLY
TWIN-SPRAY PATTERN
T880.73
AAI SYSTEM – AJ27
AIR ASSIST CONTROL VALVE
NOTES
T880.74
Student Guide
7.11
7.12
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
IGNITION
Ignition Timing and Distribution
Ignition timing and spark distribution are controlled by the ECM using a base ignition map, which is then corrected
for the specific engine operating conditions. The spark plug for each cylinder is fired by an on-plug ignition coil.
Two ignition modules, one for each group of 4 cylinders., provide the primary side switching for the coils, as signaled by the ECM. Ignition is synchronized using the input signals from the CKPS and CMPS.
Engine Firing Order
A1 – B1 – A4 – A2 – B2 – A3 – B3 – B4
Base Ignition Map
IGNITION TIMING STRATEGY (TYPICAL)
•
•
IGNITION TIMING
BASE MAP
ENGINE SPEED
•
ENGINE LOAD
PRIMARY
IGNITION TIMING
•
ENGINE CRANKING
The base ignition map sets the base ignition timing
for the full range of engine load and speed.
Engine load is determined by measuring intake
mass air flow.
The MAFS supplies the ECM with a mass air flow
signal.
The ECM receives an engine speed signal from the
CKPS.
Engine Starting
ENGINE COOLANT TEMP.
•
INTAKE AIR TEMP.
ENGINE TRANSIENTS
CORRECTION
FACTORS
Ignition timing is fixed at one value for starting
when the ECM receives an ENGINE CRANK signal
from the BPM.
EGR OPERATION
Temperature Correction
FI CUT-OFF
TRACTION / STABILITY CONTROL
•
TRANSMISSION SHIFT
BATTERY
VOLTAGE
Ignition timing corrections are applied to the ignition map by the ECM to compensate for variations
in intake air temperature and engine coolant temperature.
Fuel injection cutoff interaction
CKPS
IGNITION TIMING AND
SYNCHRONIZATION
•
CMPS
•
AJ26
AJ27
MODULE 1
MODULE 2
IGNITION MODULES
Just prior to fuel injection cutoff, the ECM retards
the ignition timing to provide a smooth transition
between the two operating states.
As fuel injection is reinstated, the ECM progressively returns the ignition timing to nominal.
NOTES
INDIVIDUAL
IGNITION MODULES
T880.77
8.2
Student Guide
Service Training
BASE IGNITION MAP (TYPICAL)
IGNITION ANGLE
ED
SPE
INE
ENG
LOA
D
T880.78
Transient Interaction
During throttle transients (idle, steady state, acceleration, deceleration), the ECM applies ignition timing correction.
The amount of timing correction depends on the throttle valve angle rate of change, and on the direction of throttle
valve movement (opening / closing).
Variable Valve Timing Operation
During VVT transition, the ECM retards ignition timing to prevent transient ignition detonation.
EGR Operation
During EGR operation, the ECM advances ignition timing. The diluted combustion chamber charge requires more
“burn time” and, therefore, more advanced ignition timing. The degree of ignition advance is proportional to engine
load and speed.
Shift Energy Management
Ignition intervention is used for shift energy management.
Traction / Stability Control
Ignition intervention is used for traction / stability control.
Misfire Detection / CAN Data
The ECM is able to detect misfire by monitoring crankshaft acceleration (CKPS signal). In order to reduce the possibility of false misfire diagnosis, the ECM uses the ABS/TCCM CAN data – left and right rear wheel speeds – to
determine if the vehicle is operating on a rough road.
Student Guide
8.3
Service Training
IGNITION
Ignition Coils and Modules – AJ26
Two ignition modules (amplifiers) are installed. The modules receive ignition drive signals from the ECM and, in turn
control the primary current switching of the on-plug ignition coils. Dwell control for the ignition system is performed within the ECM.
• Module 1 switches coils A1, A4, B2, B3.
• Module 2 switches coils A2, A3, B1, B4.
IGNITION ARRANGEMENT – AJ26
A BANK
ON-PLUG IGNITION COILS
A1
A2
A3
A4
IGNITION MODULE 1
NOMINAL 5V
PULLED LOW AT EACH SPARK
FEEDBACK
A1
B2
PRIMARY
CIRCUIT
SWITCHING
B3
A4
IGNITION
DRIVE
B1
A2
PRIMARY
CIRCUIT
SWITCHING
A3
B4
FEEDBACK
NOMINAL 5V
PULLED LOW AT EACH SPARK
IGNITION MODULE 2
B1
B2
B3
B4
B BANK
ON-PLUG IGNITION COILS
8.4
Student Guide
T880.79
Service Training
IGNITION COILS AND MODULES – XK8 AJ26
T880.80
IGNITION MODULES – XJ8 AJ26
T880.80B
NOTES
Student Guide
8.5
Service Training
IGNITION
Ignition Coil-on-Plug Units – AJ27
•
COIL-ON-PLUG IGNITION UNIT – AJ27
•
•
•
•
•
•
•
T880.82
Each AJ27coil-on-plug unit incorporates its own
ignition module.
The ignition modules are triggered directly from
the ECM and drive the coil primary circuit, controlling current amplitude, switching point and dwell.
Each ignition module provides a monitor output to
the ECM.
When an ignition trigger signal is received, an
acknowledge pulse is sent to the ECM if the current
drive to the coil primary is satisfactory.
This pulse is initiated when the current reaches 2
amps and is terminated at 4 amps.
If the trigger signal is not received or the coil current does not rise to 2 amps, the monitor line will
remain at logic high, signaling an ignition failure to
the ECM.
As with AJ26, two ignition monitor inputs (one per
group of four ignition coils) are provided to the ECM.
Ignition monitor circuits from cylinders 1A, 2B, 3B
and 4A are spliced together; ignition monitor circuits from cylinders 1B, 2A, 3A and 4B are spliced
together.
NOTES
8.6
Student Guide
Service Training
IGNITION ARRANGEMENT – AJ27
A BANK IGNITION MODULES AND COILS
1A
2A
3A
4A
IGNITION
DRIVE
1A, 2B, 3B, 4A
FEEDBACK
5V AT EACH SPARK
1B, 2A, 3A, 4B
FEEDBACK
5V AT EACH SPARK
B+
B+
E
IGNITION COIL
RELAY
IGNITION
DRIVE
ENGINE
CONTROL MODULE
1B
2B
3B
4B
B BANK IGNITION MODULES AND COILS
T880.82B
NOTES
Student Guide
8.7
Service Training
IGNITION
Ignition Knock (Detonation) Control
•
KNOCK SENSORS – AJ26
•
•
•
•
•
A BANK
B BANK
•
•
The ECM retards ignition timing to individual cylinders to control ignition knock (detonation) and
optimize engine power.
Two knock sensors (KS) are positioned on the cylinder block in the engine vee to sense engine detonation.
One KS is positioned on A bank and the other on B
bank.
Each knock sensor has a piezo electric sensing element to detect broad band (2 – 20 kHz) engine
accelerations.
If detonation is detected, between 700 and 6800
rpm, the ECM uses the crankshaft position sensor
(CKPS) signal to determine which cylinder is firing,
and retards the ignition timing for that cylinder only.
If, on the next firing of that cylinder, the detonation reoccurs, the ECM will further retard the ignition timing; if the detonation does not reoccur on
the next firing, the ECM will advance the ignition
timing incrementally with each firing.
The knock sensing ignition retard / advance process can continue for a particular cylinder up to a
maximum retard of 9.4 degrees.
During acceleration at critical engine speeds, the
ECM retards the ignition timing to prevent the
onset of detonation. This action occurs independent of input from the knock sensors.
T880.81
NOTES
8.8
Student Guide
Knock Sensors (KS) – AJ27
•
•
•
Service Training
KNOCK SENSORS – AJ27
The AJ27 sensors are of an annular (doughnut) construction and are mounted via a stud and nut to the
cylinder head.
To improve cylinder identification, particularly at
higher engine RPM, switched capacitive filters are
incorporated in the ECM.
Knock sensing performance is further enhanced by
the use of improved ECM signal processing software.
T880.83
Knock Sensing OBD Monitoring
KS sense circuit out of range (low voltage)
With the ignition switched ON, the ECM monitors the A bank KS signal for low voltage. If the signal voltage is less
than 0.6V on the first trip, the ECM takes default action. If the signal voltage is less than 0.6V on two consecutive
trips, the ECM flags a KS DTC and the CHECK ENGINE MIL is activated.
Default action: the ECM sets ignition retard to maximum.
KS sense circuit out of range (high voltage)
With the ignition switched ON, the ECM monitors the A bank KS signal for high voltage. If the signal voltage is greater than 4.15V on the first trip, the ECM takes default action. If the signal voltage is greater than 4.15V on two
consecutive trips, the ECM flags a KS DTC and the CHECK ENGINE MIL is activated.
Default action: the ECM sets ignition retard to maximum.
NOTES
Student Guide
8.9
8.10
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
Variable Valve Timing – AJ26
The AJ26 two-position variable valve timing (VVT) system improves low and high speed engine performance, idle
quality, and exhaust emission. VVT is a two-position system that operates on the intake camshafts only. There are
30° of crankshaft rotation between the retarded and the advanced positions. The system is operated by engine oil
pressure under the control of the ECM. The VVT hardware associated with each intake camshaft includes:
• Valve timing unit
• Bush carrier assembly
• Valve timing solenoid
VARIABLE VALVE TIMING – AJ26 (CRANKSHAFT ROTATION SHOWN)
RETARDED
ADVANCED
TDC
TDC
5˚
35˚
5˚
10˚
25˚
INTAKE
EXHAUST
65˚
50˚
INTAKE
50˚
35˚
BDC
BDC
T880.84
Valve Timing Unit
VALVE TIMING UNIT – AJ26
BODY AND SPROCKET
ASSEMBLY
10˚
EXHAUST
•
INNER
SLEEVE
BACKLASH
SPRING
•
RETURN
SPRING
•
•
•
The valve timing unit rotates the intake camshaft in
relation to the primary chain to advance or retard
the intake valve timing.
The unit is made up of a body and sprocket assembly separated from an inner sleeve by a ring piston
and two ring gears.
A bolt secures the inner sleeve to the camshaft
The ring gears engage in opposing helical splines
on the body and sprocket assembly, and on the
sleeve.
The ring gears transmit the drive from the body
and sprocket assembly to the inner sleeve and,
when moved axially, rotate the inner sleeve in
relation to the body and sprocket assembly.
PISTON
RING GEARS
9.2
T880.85
Student Guide
Service Training
Engine oil pressure ported by the valve timing solenoid moves the ring gears and piston to rotate the inner sleeve in
the advance timing direction. A return spring moves the ring gears and piston to rotate the inner sleeve in the retard
timing direction.
A series of small springs absorb backlash to reduce noise and wear. The springs between the ring gears absorb rotational backlash. The springs between the inner sleeve and the end of the body and sprocket assembly absorb axial
backlash.
Bush Carrier
•
•
BUSH CARRIERS – AJ26
The bush carriers contain oil passages that link the
engine oil supply to the valve timing unit.
The integral shuttle valve, connected to the valve
timing solenoid and biased by a coil spring, controls the flow of oil through the passages.
Valve Timing Solenoid
•
•
The valve timing solenoid positions the shuttle valve
in the bush carrier.
A plunger on the solenoid extends a minimum of
6.8 mm (0.28 in.) when the solenoid is energized
and retracts when the solenoid is deenergized.
T880.86
NOTES
VALVE TIMING SOLENOID – AJ26
T880.87
Student Guide
9.3
Service Training
Variable Valve Timing – AJ26
VVT Mechanical Operation
VARIABLE VALVE TIMING OPERATION – AJ26
Intake valve timing retarded
• When the valve timing solenoids are de energized,
the coil springs in the bush carriers position the
shuttle valves to port the valve timing units to drain.
• The valve timing units return springs hold the ring
pistons and gears in the retarded position.
RETARDED
Intake valve timing advanced
• When the valve timing solenoids are energized, the
solenoid plungers position the shuttle valves to
port pressurized engine lubricating oil to the valve
timing units.
• The oil pressure moves the gears and ring pistons
to the advanced position.
• System response times are 1 second maximum for
advance, 0.7 second maximum for retard.
OIL RETURN
ENGINE OIL PRESSURE
ADVANCED
ECM VVT Control
•
•
•
ENGINE OIL PRESSURE
T880.88
•
•
VARIABLE VALVE TIMING MAP – AJ26
ENGINE LOAD
•
•
1
2
3
4
5
6
The ECM switches the valve timing solenoids to
advance / retard intake valve timing based on a
map of engine load and speed.
The map incorporates both engine load and speed
“hysteresis” (overlap) to prevent “hunting”.
Between 1250 and 4500 rpm (nominal), at engine
load greater than approximately 25%, the intake
valve timing is advanced.
The intake valve timing is retarded at low engine
speed and at high engine speed.
VVT is inhibited (intake valve timing remains
retarded) at engine coolant temperatures less than
-10 °C (14 °F).
While the valve timing is retarded, the ECM periodically drives the valve timing solenoid open with
a momentary pulse.
This momentary pulse occurs every five minutes,
and allows a spurt of oil flow to the valve timing
units to prevent wear. It is possible to hear the
lubrication pulse with the engine running and the
hood open.
7
ENGINE SPEED (rpm x 1000)
RETARDED
ADVANCED
T880.89
9.4
Student Guide
Service Training
Linear Variable Valve Timing – AJ27
•
•
•
The AJ27 Linear VVT system provides continuously variable inlet valve timing over a crankshaft range of 48° ±
2°.
Depending on driver demand and engine speed / load conditions, the inlet valve timing is advanced or
retarded to the optimum angle within this range.
Compared to the two position system used on AJ26, inlet valve opening is advanced by an extra 8°, providing
greater overlap and increasing the internal EGR effect (exhaust gases mixing with air in the inlet port).
LINEAR VVT – AJ27
EXHAUST
INLET
MAXIMUM ADVANCE
INLET
MAXIMUM RETARD
9
8
VALVE LIFT (mm)
7
6
5
4
3
2
1
0
0
90
180
270
360
450
540
630
720
CRANK ANGLE (degrees)
T880.90
The linear VVT system provides a number of advantages:
• Improves internal EGR, further reducing NOx emissions and eliminating the need for an external EGR system
• Optimizes torque over the engine speed range without the compromise of the two-position system: note that
specified torque and power figures are unchanged
• Improves idle quality: the inlet valve opens 10° later, reducing valve overlap and thus the internal EGR effect
(undesirable at idle speed)
• Faster VVT response time
• VVT operates at lower oil pressure
NOTES
Student Guide
9.5
Service Training
Linear Variable Valve Timing – AJ27 (continued)
Linear VVT Components
Each cylinder bank has a VVT unit, bush carrier and solenoid operated oil control valve which are all unique to the
linear VVT system. The VVT unit consists of an integral control mechanism with bolted on drive sprockets, the complete assembly being non-serviceable. The unit is fixed to the front end of the inlet camshaft via a hollow bolt and
rotates about the oil feed bush on the bush carrier casting. The bush carrier is aligned to the cylinder head by two
hollow spring dowels and secured by three bolts.
The oil control valve fits into the bush carrier to which it is secured by a single screw. The solenoid connector at the top
of the valve protrudes through a hole in the camshaft cover but the cover must first be removed to take out the valve.
Engine oil enters the lower oilway in the bush carrier (via a filter) and is forced up through the oil control valve shuttle spools to either the advance or retard oilway and through the bush to the VVT unit. Oil is also returned from the
VVT unit via these oilways and the control valve shuttle spools, exiting through the bush carrier drain holes.
NOTE: Only the bush carriers are left- and right-handed.
LINEAR VVT COMPONENTS – AJ27
SOLENOID CONNECTOR
OIL CONTROL VALVE
OIL FEED BUSH
BUSH CARRIER
OIL DRAINS
VVT UNIT
OIL FEED
VVT UNIT
FIXING BOLT
T880.91
9.6
Student Guide
Linear VVT unit
The VVT unit transmits a fixed drive via the secondary
chain to the exhaust camshaft. The inlet camshaft is driven from the body of the unit via internal helical splines:
when commanded from the ECM this mechanism rotates
the inlet camshaft relative to the body/sprocket assembly
to advance or retard the valve timing.
Service Training
LINEAR VVT UNIT – AJ27
ANTI-BACKLASH
SPRINGS
RETARD CHAMBER
OIL FEED / DRAIN
INNER SLEEVE
The VVT unit has three main parts: the body/sprocket
assembly, an inner sleeve bolted axially to the nose of
the camshaft and a drive ring/piston assembly located
between the body and inner sleeve and coupled to both
via helical splines.
The basic operation is similar to that of the two position
unit: oil pressure applied in the advance chamber forces
the drive ring/piston assembly to move inwards along its
axis while rotating clockwise on the helical body splines.
Since the drive ring is also helically geared to the inner
sleeve but with opposite angled splines, the inner sleeve
is made to rotate in the same direction, turning the camshaft. The use of opposing helical gears (the angle is
more acute than in the two position unit) produces a relatively large angular rotation for a small axial movement,
thus keeping the VVT unit to a compact size. Note that
the inner sleeve does not move axially.
PISTON RETURN
SPRING
ADVANCE CHAMBER
OIL FEED / DRAIN
ADVANCE CHAMBER
DRIVE RING
AND PISTON ASSEMBLY
T880.92
To move back to a retard position, oil pressure is switched to the retard chamber and the piston and rotational
movements are reversed. The use of oil pressure to move the piston in both directions eliminates the need for a
return spring for VVT operation (as in the two position system). However, a lighter pressure spring is fitted in the
retard chamber to assist the piston assembly to revert to the fully retarded position with the engine stopped. Note
that rotating the engine backwards from the stopped position will cause the VVT unit body to move relative to the
camshaft, advancing the timing. To avoid the possibility of incorrect timing being set after any associated service
work, reference must be made to JTIS for the correct procedures.
Due to the use of bidirectional oil pressure actuation and light spring pressure, a much lower oil pressure is required
to advance the VVT unit, making its operation more consistent at high oil temperatures/low engine speed. Also,
response times to move in the advance direction are reduced by approximately 50% compared with the two position actuator.
NOTES
Student Guide
9.7
Service Training
Linear Variable Valve Timing – AJ27 (continued)
Linear VVT Oil Control – Advance
•
•
To fully advance the cams, the solenoid is energized pushing the shuttle valve down.
This action causes the incoming oil feed to be directed through the lower oilway in the bush carrier and into
the advance oil chamber where it pushes on the piston/drive ring assembly.
As the piston moves in the advance direction (towards the camshaft), oil is forced out of the retard chamber
through oilways in the sprocket unit, camshaft, hollow fixing bolt, bush carrier and the shuttle valve from
which it drains into the engine.
•
Linear VVT Oil Control – Retard
•
To move to the fully retarded position, the solenoid is de-energized, the return spring holds the shuttle valve in
its upper position and the oil flow is directed through the bush carrier upper oilway into the VVT unit.
Oil is channeled through the hollow VVT fixing bolt and via oilways in the camshaft and sprocket unit to the
retard chamber where it acts on the moveable piston/drive ring assembly.
As the piston moves, oil is forced from the advance chamber back through the shuttle valve to the engine.
•
•
LINEAR VVT OIL CONTROL – AJ27
VVT UNIT IN FULLY ADVANCED POSITION
VVT
SOLENOID VALVE
DRIVE RING AND
PISTON ASSEMBLY
BUSH CARRIER
RETARD CHAMBER
VVT UNIT FIXING BOLT
OIL DRAINS
CAMSHAFT
ROTATION
TO ADVANCE
OIL FEED
FOUR-SPOOL
SHUTTLE VALVE
CAMSHAFT
VVT UNIT IN FULLY RETARDED POSITION
CAMSHAFT
ROTATION
TO RETARD
OIL FEED
OIL DRAINS
T880.93
9.8
Student Guide
Service Training
Linear VVT ECM Control System
Closed loop control
• Continuously variable timing requires the VVT piston to be set to the optimal position between full advance
and retard for a particular engine speed and load.
• The ECM positions the shuttle valve using a PWM control signal operating at a frequency of 300 Hz.
• The shuttle valve assumes a position between the limits of travel proportional to the “duty cycle” of the signal.
An increasing duty cycle causes an increase in timing advance.
• The shuttle valve is continuously controlled by the ECM to maintain a given cam angle. The actual position of
the camshaft is monitored by a magnetic sensor which generates pulses from the toothed sensor ring keyed on
to the end of the camshaft and transmits them to the ECM. If a difference is sensed between the actual and
demanded positions, the ECM will attempt to correct it. The new cam sensor fitted to A bank allows each bank
to have its own feedback loop. The four tooth cam sensor rings increase the cam position feedback frequency,
providing the enhanced control required by the new VVT system. The use of four-tooth sensor rings also
improves starting (see Engine Management Sensors).
Engine oil temperature
Engine oil properties and temperature can affect the ability of the VVT mechanism to follow demand changes to the
cam phase angle. At very low oil temperatures, movement of the VVT mechanism is sluggish due to increased viscosity and at high temperatures the reduced viscosity may impair operation if the oil pressure is too low.
The VVT system is normally under closed loop control except in extreme temperature conditions such as cold starts
below 0 °C (32 °F). At extremely high oil temperatures, the ECM may limit the amount of VVT advance to prevent
the engine stalling when returning to idle speed. This could occur because of the slow response of the VVT unit to
follow a rapid demand for speed reduction. Excessive cam advance at very light loads produces high levels of internal EGR which may result in unstable combustion or misfires.
Engine oil temperature sensor (EOTS)
The EOTS is a thermistor which has a negative temperature coefficient (NTC). Engine oil temperature is
determined by the ECM by the change in the sensor
resistance. The sensor is located on the engine block
directly above the oil pressure switch.
EOTS – AJ27
The ECM applies 5 volts to the sensor and monitors the
voltage across the pins to detect the varying resistance.
The ECM uses the EOT signal for variable valve timing
control.
NOTES
T880.94
Student Guide
9.9
9.10
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
EXHAUST GAS RECIRCULATION
Exhaust Gas Recirculation – AJ26
Exhaust gas recirculation (EGR) was fitted to 1997 model year XK8 vehicles and was deleted during the same
model year.
EGR VALVE – AJ26
NOTE: EGR is fitted to AJ26 and AJ27 supercharged engines.
EGR lowers combustion temperature, which in turn
reduces NOx exhaust emission. EGR is controlled by
the ECM from a map that factors engine operating conditions such as engine load and speed, throttle position,
and coolant temperature.
The EGR valve is mounted directly to the intake air
induction elbow and connects to the A bank exhaust
manifold by a transfer pipe. The EGR valve contains a
four-pole stepper motor (60 step), which is driven by
the ECM. Engine coolant returning from the throttle
assembly is channeled through the valve to provide
cooling.
NOTES
T880.95
10.2
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
OTHER ECM CONTROL AND INTERFACE FUNCTIONS
Engine Cranking / Starting (Normally Aspirated Engines)
When the ignition is switched ON (position II) and the transmission manual valve is in Park or Neutral, the ECM
enables fuel injection and ignition, and outputs a “security acknowledge” encoded signal to the BPM. The Park /
Neutral signal is received via the hard wired circuit from the transmission rotary switch. If the BPM receives a Park /
Neutral signal from the gear selector neutral switch, it in turn, enables engine cranking. When the ignition key is
moved to CRANK (position III) and the gear selector is in Park or Neutral, the BPM drives the starter relay to crank
the engine. The ECM receives a “cranking” signal from the BPM / starter relay drive circuit. The ECM initiates engine
start EMS values for the duration of the cranking signal.
Supercharged engines Both Park and Neutral signals are supplied from the dual linear switch located at the J gate.
Vehicles without Key Transponder Module (KTM) (1997 Model Year)
If the transmission manual valve is not in Park or Neutral (rotary switch signal) at ignition ON, the ECM inhibits fuel
injection and ignition, and does not transmit the “security acknowledge” signal to the BPM.
Vehicles with Key Transponder Module (KTM)
If the transmission manual valve is not in Park or Neutral (rotary switch signal) at ignition ON, and/or the KTM does
not transmit an encoded “security acknowledge” signal to the ECM and the BPM, the ECM inhibits fuel injection and
ignition, and does not transmit the “security acknowledge” signal to the BPM.
NOTES
11.2
Student Guide
Service Training
ENGINE CRANKING / STARTING
SECURITY
DISARM
S
NOT-IN-PARK SWITCH
(GEAR SELECTOR)
B+
BPM
IGNITION B+
POSITION III
STARTER RELAY
POSITION II
POSITION I
KEY IN
IGNITION SWITCH
D
B+
B+
SECURITY
ACKNOWLEDGE
KTM
D
IGNITION KEY /
TRANSMITTER
STARTER MOTOR
D
READER /
EXCITER COIL
D
ECM
P/N SWITCH
(TRANSMISSION)
T880.95B
Student Guide
11.3
Service Training
OTHER ECM CONTROL AND INTERFACE FUNCTIONS
Radiator Cooling Fan Control
The ECM controls the radiator cooling fan operation. Using inputs from the air conditioning refrigerant four-way
pressure switch and the ECTS, the ECM drives the fans in series (low speed) or in parallel (high speed). The four-way
pressure switch contains a 12 bar (174 psi) switch element and a 22 bar (319 psi) switch element connected to the
ECM. A two-pressure switch element signals the A/CCM for compressor operation.
As the ECM switches the fans, “hysteresis” or overlap between switch on / switch off prevents “hunting” between the
fan modes.
Radiator Fan Switching Points
Mode
Engine coolant temperature
ON
OFF
Refrigerant pressure
ON
OFF
• SLOW (SERIES)
• 90 °C (194 °F)
• 86 °C (187 °F)
• 12 bar (174 psi)
• 8 bar (116 psi)
• FAST (PARALLEL)
• 97.5 °C (207.5 °F)
• 93.5 °C (200.5 °F)
• 22 bar (319 psi)
• 17.5 bar (254 psi)
If the fans are operating when the engine is switched off, the ECM continues to drive the fans for up to five minutes or until
the engine coolant temperature has fallen to a predetermined value, whichever occurs first. If the fans are off when the
engine is switched off and the coolant temperature rises to the switch-on point during the few seconds time the ECM
remains powered to complete throttle adaptions, the fans will switch on and continue to operate for up to five minutes, or
until the engine coolant temperature has fallen to a predetermined value, whichever occurs first.
RADIATOR COOLING FAN CONTROL
ENGINE COOLANT
TEMPERATURE SENSOR
LOW SPEED
FAN RELAY
RIGHT FAN
LOW SPEED ON
12 BAR (174 PSI)
FAN
CONTROL
HIGH SPEED ON
22 BAR (319 PSI)
HIGH SPEED
FAN RELAY
REFRIGERANT 4-WAY
PRESSURE SWITCH
ENGINE CONTROL
MODULE
LEFT FAN
FAN CONTROL
RELAY MODULE
T880.95C
NOTES
11.4
Student Guide
Service Training
Air Conditioning Compressor Clutch Control
The ECM controls the operation of the air conditioning compressor clutch to prevent idle instability and over heating. The air conditioning control module (A/CCM) determines when compressor clutch operation is required and
signals the ECM via the A/C compressor clutch request hard wire circuit. Depending on the engine operating conditions, the ECM drives the air conditioning compressor clutch relay to operate the air conditioning compressor. The
A/CCM receives confirmation that the compressor is operating from the clutch relay parallel power circuit.
Engine conditions for compressor ON:
• Engine not at idle*
• Engine coolant temperature not greater than a programmed high temperature
• Throttle valve less than full load (WOT)
*Engine at idle – There is a momentary delay (approximately 50 ms) before the ECM drives the compressor
clutch relay. This delay allows the ECM to compensate the idle speed for the impending high load.
Engine conditions for compressor OFF:
• Engine coolant temperature greater than a programmed high temperature
• Throttle valve at full load (WOT)
When the compressor clutch operation is inhibited, the ECM outputs a load inhibit signal to the A/CCM via the load
inhibit hard wire circuit.
Windshield and Backlight Heaters Control
The ECM can also inhibit the operation of the windshield and backlight heaters to prevent idle instability. When the
driver selects the heaters ON, the A/CCM signals the ECM for permission to switch ON the heaters via the electrical
load request hard wire circuit. Depending on the engine operating conditions, the ECM inhibits heater operation by
outputting a load inhibit signal to the A/CCM via the load inhibit hard wire circuit.
Engine conditions for heaters ON:
• Engine not at idle*
• Engine coolant temperature not greater than a programmed high temperature
• Throttle valve less than full load (WOT)
*Engine at idle – There is a momentary delay (approximately 50 ms) before the ECM cancels the load inhibit
signal. This delay allows the ECM to compensate the idle speed for the impending high load.
Engine conditions for heaters inhibited:
• Engine coolant temperature greater than a programmed high temperature
• Throttle valve at full load (WOT)
When the heaters are inhibited, the ECM outputs a load inhibit signal to the A/CCM via the load inhibit hard wire circuit.
NOTES
Student Guide
11.5
11.6
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
Service Training
AJ26 / AJ27 SUPERCHARGED EMS
AJ V8 Supercharged Engine
The AJ V8 supercharged (SC) engine is essentially mechanically identical to the normally aspirated engine with the
exception of the pistons, the cylinder head gaskets and the repositioning of components to allow installation of the
supercharger system. The normally aspirated intake manifold and induction elbow are replaced with unique supercharged components.
SUPERCHARGER INSTALLATION
‘B’ BANK
CHARGE AIR COOLER
CONNECTING DUCT AND
CLAMP PLATE
OUTLET DUCT
‘A’ BANK
CHARGE AIR COOLER
SUPERCHARGER
VACUUM TAKEOFF
T880.96
The supercharger is an Eaton M112 “Roots Type” unit mounted in the engine vee, driven by a separate poly v-belt
from the crankshaft. Supercharger lubrication is “filled for life”. If servicing of the lubricant is required, the supercharger must be removed from the engine. The maximum boost pressure is 0.8 bar (11.6 psi).
Intake air flows through a revised mass air flow sensor (MAFS), through the intake duct, the electronic throttle assembly and the induction elbow to the supercharger. The AJ26 SC throttle assembly is unchanged from the normally
aspirated system with EGR. The AJ27 SC throttle deletes AAI and adds EGR. A bypass valve attaches to the induction
elbow. From the supercharger, compressed intake air flows through the outlet duct to the individual A and B bank airto-liquid charge air coolers, then through the A and B bank charge air cooler adapters to the cylinder heads.
NOTES
12.2
Student Guide
Service Training
SUPERCHARGED INTAKE SYSTEM
THROTTLE ASSEMBLY
BYPASS VALVE ACTUATOR
M
BYPASS VALVE
SUPERCHARGER
CHARGE AIR COOLER
COOLANT FLOW
T880.97
Student Guide
12.3
Service Training
Supercharger Mechanical Components
Bypass Valve and Actuator
BYPASS VALVE AND ACTUATOR – AJ26
The “butterfly” bypass valve is contained in a housing
attached to the induction elbow. The valve is operated
by a vacuum actuator. The valve controls bypass air
flow from the charge air coolers to the induction elbow
in order to regulate supercharger “boost pressure”. The
valve is held closed by spring pressure.
With closed (idle) or partially open (cruise) throttle,
intake vacuum (between the induction elbow and the
supercharger) acts on the actuator diaphragm to hold
the valve full open to provide maximum supercharger
bypass and optimum fuel economy. As the throttle is
opened, intake vacuum falls progressively and spring
force moves the valve toward closed until the valve is
fully closed at full throttle, providing maximum supercharger boost and power.
T880.98
Outlet Duct
The supercharger outlet duct directs the charge air from
the supercharger to the two charge air coolers. The fill
point and connections for the charge air cooler coolant
circuit are integrated into the outlet duct. Vacuum
source is provided for the fuel pressure regulator and
for cruise control. Rubber ducts secured by clamp
plates connect the outlet duct to the two charge air
coolers.
THROTTLE INDUCTION ELBOW – AJ27
NOTES
T880.99
12.4
Student Guide
Service Training
Charge Air Coolers
Each cylinder bank has a separate charge air cooler assembly. The charge air coolers are fabricated fin and tube airto-liquid heat exchangers with individual “risers” to supply charge air to each cylinder. The charge air coolers cool
the charge air leaving the supercharger to increase the mass of the air entering the engine. Coolant flow is provided
by a separate cooling system with an electric pump under ECM control.
Charge air cooler adapters / fuel rails
The charge air cooler adapters provide the interface between the charge air coolers and the cylinder heads, and
incorporate the fuel rails and fuel injector mountings. A crossover pipe connects the fuel rails.
SUPERCHARGER CHARGE AIR COOLER, ADAPTER AND FUEL RAIL
CHARGE AIR COOLER
GASKET
FUEL RAIL AND
CHARGE AIR COOLER ADAPTER
T880.100
Fuel Injectors
The fuel injectors are high flow units designed for the supercharged engine. They are secured in the fuel rails by
spring clips.
NOTES
Student Guide
12.5
Service Training
Supercharger Mechanical Components (continued)
Charge Air Cooler Radiator and Pump
The charge air cooler radiator is mounted ahead of the engine radiator and incorporates a bleed outlet and a purge cock.
CHARGE AIR COOLER RADIATOR
BLEED OUTLET
PURGE COCK
T880.101
NOTES
12.6
Student Guide
Charge Air Cooler Coolant Pump
Service Training
CHARGE AIR COOLER AND PUMP
The charge air cooler coolant pump is activated via a
relay under ECM control. During normal conditions,
the ECM operates the pump continuously with the ignition switched ON.
NOTES
T880.102
Student Guide
12.7
Service Training
The supercharged Engine Management System is essentially identical to the normally aspirated system with software revisions to accommodate the operating characteristics of the supercharged engine. Additional functions for
operating two fuel pumps, the charge air cooler coolant pump, and EGR are included. Variable valve timing and air
assisted fuel injection (AJ27) are deleted.
Components / Functions deleted for Supercharged Engine Management:
• Variable valve timing
• Air assisted fuel injection (AJ27)
Components / Functions added for Supercharged Engine Management
• Two fuel pumps
• Charge air cooler coolant pump
• Exhaust gas recirculation
• Second intake air temperature sensor (charge air temperature sensor)
Supercharged EMS Components
Fuel Pumps
Two fuel pumps are used to provide adequate fuel flow during high engine loads. Both pumps are operated by the
ECM via relays. Operation of fuel pump 1 is identical to the normally aspirated single fuel pump. Diagnostic monitoring for the N/A single fuel pump remains unchanged. The other warnings and default action differs for the SC
pump 1. Fuel pump 2 is switched by the ECM as determined by engine operating conditions. Refer to page 6.5 for
fuel pump details.
NOTES
12.8
Student Guide
Intake Air Temperature Sensor 2 (IATS 2)
Service Training
CHARGE AIR COOLER IATS 2
A separate intake air temperature sensor (IATS 2), located on the A bank charge air cooler outlet, provides the
ECM with a “charge air” temperature signal.
As with previous air temperature sensors, the IATS 2 is a
negative temperature coefficient (NTC) thermistor.
Charge air temperature is determined by the ECM by a
change in sensor resistance. The ECM applies 5 volts to
the sensor and monitors the voltage across the pins to
detect the varying resistance.
The IATS located within the MAFS remains active in the
system and is used for diagnostic purposes.
IATS air temperature / resistance / voltage
Temperature
°C
°F
Resistance
Voltage
- 40
- 40
53.1kΩ
4.75
- 30
- 22
28.6kΩ
4.57
- 20
-4
16.2kΩ
4.29
-10
14
9.6kΩ
3.90
0
32
5.9kΩ
3.43
10
50
3.7kΩ
2.89
20
68
2.4kΩ
2.38
30
86
1.7kΩ
1.93
40
104
1.1kΩ
1.45
50
122
810Ω
1.15
60
140
580Ω
0.88
70
158
430Ω
0.69
80
176
320Ω
0.53
90
194
240Ω
0.41
100
212
190Ω
0.33
110
230
150Ω
0.26
120
248
120Ω
0.21
T880.103
ECTS – AJ V8 SUPERCHARGED
T880.104
Engine Coolant Temperature Sensor (ECTS)
On supercharged engines, the ECTS is relocated to
accommodate the supercharger installation.
Student Guide
12.9
Service Training
The AJ26 SC EMS uses the same EGR system as early
production naturally aspirated engines.
EGR VALVE – AJ26
Exhaust gas recirculation lowers combustion temperature, which in turn reduces NOx exhaust emission.
EGR is controlled by the ECM from a map that factors
engine operating conditions such as engine load and
speed, throttle position, and coolant temperature.
The EGR valve is mounted directly to the intake air
induction elbow and connects to the A bank exhaust
manifold by a transfer pipe. The EGR valve contains a
four-pole stepper motor (60 step), which is driven by
the ECM. Engine coolant returning from the throttle
assembly is channeled through the valve to provide
cooling.
NOTES
T880.105
12.10
Student Guide
Service Training
EGR VALVE – AJ27
The AJ27 SC EGR system provides increased exhaust gas
flow over the AJ26 SC system. ECM control is enhanced
by an EGR flow monitoring feedback signal.
COOLANT PIPES
Manifold Absolute Pressure Sensor (MAPS)
AJ27 EGR systems include a MAP sensor, which enables
the ECM to monitor EGR gas flow into the intake manifold. When the EGR valve opens to allow exhaust gas
flow into the throttle elbow, the intake manifold absolute pressure will drop directly proportional to the
amount the valve is open. The ECM applies 5 volts to
the MAP sensor, which produces a linear output voltage signal to the ECM.
EGR VALVE
TRANSFER PIPE
NOTES
T880.106
MAP SENSOR – AJ27
T880.108
MAP SENSOR CHARACTERISTIC – AJ27
VOLTAGE
3.96
1.2
0.20 bar
5.9 in. hg.
ABSOLUTE PRESSURE
1.12 bar
33.07 in. hg.
T880.107
Student Guide
12.11
12.12
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
AJ26 / AJ27
AJ26/27
1
2
CONTROL SUMMARIES
3
4
5
6
FUEL DELIVERY AND
7
FUEL INJECTION
8
IGNITION
9
NORMALLY ASPIRATED
INTERFACE FUNCTIONS
13 TASK SHEETS
z
880 - V8/V6 Engine Management
Service Training
AJ27 - VVT System
Name:_______________________ Date:____________ Vehicle/VIN__________________
Perform procedure with parking brake on & exhaust extraction hoses connected.
1. Reference the correct Electrical Guide, identify and mark the pin numbers and wire colors for each VVT circuit per cylinder bank.
Bank B= ________________________________ Bank A = ____________________________
EM80
EM81
EM82
EM83
EM84
EM85
EM80
9
8
7
21
20
19
31
30
29
9
8
7
19
18
17
28
27
26
6
18
5
17
16
28
27
EM81
4
15
3
2
1
7
6
5
14
13
12
11
10
16
15
14
26
25
24
23
22
24
23
22
EM83
4
13
EM82
3
2
1
6
5
4
3
2
1
11
10
9
8
7
16
15
14
13
3
2
1
8
7
6
12
11
10
9
8
12
21
20
19
18
17
17
EM85
EM84
6
5
4
3
2
1
7
6
16
15
14
13
12
11
10
15
14
25
24
23
22
21
20
22
21
5
4
3
2
1
5
4
13
12
11
10
9
8
12
11
20
19
18
17
16
10
9
2. Using a DVOM capable of measuring frequency, set the meter to DC volts - Hz.
3. Back probe the red lead of the meter to one VVT control circuit at the ECM.
4. With the key on engine off, check and record the signal frequency: ________________.
Is it a fixed frequency?: Yes [ ] No [ ]
5. Start engine and allow to idle. Switch the DVOM to duty cycle, what is the value?:_________
6. Increase the engine speed to 2500 RPM. What is the value?: _____________
7. Switch the engine off, measure the resistance (Ω) of each solenoid: _______________
“continued”
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 - VVT System (Page 2)
8. Reference the correct DTC Summary Guide. List the DTCs that identify VVT system
malfunction.
9. When the identified DTCs are stored, what is the default action of the ECM for each
DTC.
10. List the possible malfunctions associated with each DTC.
Instructor Check: ____________________________
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 SC - Fuel Pressure Testing & SC Boost Demo
Tools needed: Fuel pressure gauge and Vacuum gauge
1. Depressurize Fuel Rail. Install a fuel pressure gauge to the fuel rail and check for leaks.
Install a vacuum gauge with T fitting to the vacuum supply at the fuel pressure regulator.
2. Key on. What is the displayed fuel pressure: _______________bar (psi)
3. Start engine and idle. What is the displayed fuel pressure: ________________bar (psi).
4. Quickly step on the accelerator pedal and release.
• What is the max fuel pressure: _______bar (psi).
• What is the vacuum gauge positive pressure reading: ________________
• What causes the pressure increases:
5. With the engine running, disconnect the vacuum hose from fuel pressure regulator,
What is the pressure value: ____________bar (psi)
6. Switch the ignition off. Observe the pressure gauge reading and describe what happens
to the pressure value after 1 minute. _______________. Is this normal, [ ] Yes, [ ] No.
Instructor Check: ______________________
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 - Air Assist Close Valve
1. Locate and identify the AAIC valve on the engine. What is it’s functional purpose:
2. Reference the correct Electrical Guide, identify and mark the pin numbers and wire colors for the AAIC valve.
Power = _______________ Ground = ________________ Control = _______________
EM80
EM81
EM82
EM83
EM84
EM85
EM80
9
8
7
21
20
19
31
30
29
9
8
7
19
18
17
28
27
26
6
18
5
17
16
28
27
EM81
4
15
3
2
1
7
6
5
14
13
12
11
10
16
15
14
26
25
24
23
22
24
23
22
EM83
4
13
EM82
3
2
1
6
5
4
3
2
1
10
9
8
7
15
14
13
3
2
1
8
7
6
12
11
10
9
8
12
11
21
20
19
18
17
17
16
EM85
EM84
6
5
4
3
2
1
7
6
16
15
14
13
12
11
10
15
14
25
24
23
22
21
20
22
21
5
4
3
2
1
5
4
13
12
11
10
9
8
12
11
20
19
18
17
16
10
9
3. Using a DVOM capable of measuring frequency, set the meter to DC volts - Hz.
4. Connect the meter to the AAIC control circuit pin and to ground at the ECM.
5. With the key on engine off, check and record the signal frequency: ________________.
Is it a fixed frequency: Yes [ ] No [ ]
6. (Simulated Cold Engine) Start the engine and monitor the engine temperature.
Check and record the monitored frequency of the AAIC control signal ____________Hz.
Is it a fixed frequency: Yes [ ] No [ ]
7. Start engine and allow to idle. What is the displayed duty cycle? _____________________
8. Increase the engine speed to 2500 RPM. What is the displayed duty cycle? ___________
9. Measure the voltage at the control circuit pin: _________________
“Continued on Back”
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 - Air Assist Close Valve (Page 2)
10. (Simulate Warm Engine) Check and record the monitored frequency of the AAIC
control signal ____________Hz. Is it a fixed frequency: Yes [ ] No [ ]
11. Increase the engine speed to 2500 RPM. What is the displayed duty cycle_________
12. Measure the voltage at the control circuit pin: __________________________________
13. Switch engine off. What is the resistance value of the AAI __________
14 Reference the correct DTC Summary Guide. List the DTCs that identify AAI system
malfunction.
15. When the identified DTCs are stored, what is the default action of the ECM for each
DTC.
16. List the possible malfunctions associated with each DTC.
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 - DTC Summaries
1. What does P1000 and P1111 identify.
2. What is system readiness. _____________________________________________________.
3. How can system readiness information help you diagnose a vehicle that has an emission related DTC stored in memory.
4. Elaborate on DTC P1250.
• Is it an OBD II Fault: Yes [ ] No [ ]
• Will the Check Engine Light illuminate when this fault is stored: Yes [ ] No [ ]
•Does the ECM require two trips with the fault present to store this DTC: Yes [ ] No [ ]
•Will any messages be displayed in the Instrument Cluster with this DTC: Yes [ ] No [ ]
•If “Yes” please list the messages.
5. Referring to the correct Wiring Guide, list the pin numbers and wire colors for the following components/signals:
•CCV:_______________________________________________________________________
•FTPS:______________________________________________________________________
•MAFS:______________________________________________________________________
•EOT:_______________________________________________________________________
•ECT:_______________________________________________________________________
•CKPS:______________________________________________________________________
•CMPS:____________________________________________________________________
Instructor Check:
Student Workbook
880 Worksheet.fm
z
Service Training
AJ27 - Component Monitoring
1. Using the correct Wiring Guide, identify the component acronyms, their pin numbers
and wire colors at the ECM for the components listed in the table below.
2. Use connector illustration to help locate the pins at the ECM when measuring signal.
EM80
EM81
EM82
EM83
EM84
EM85
EM80
9
8
7
21
20
19
31
30
29
9
8
7
19
18
17
28
27
26
6
18
5
EM81
4
17
16
28
27
15
3
2
1
14
13
12
11
10
26
25
24
23
22
7
6
5
16
15
14
24
23
22
EM83
4
13
EM82
3
2
1
12
11
10
9
8
21
20
19
18
17
5
4
3
2
1
7
6
16
15
14
13
12
11
10
15
14
25
24
23
22
21
20
22
21
5
4
3
2
1
12
11
10
9
8
7
17
16
15
14
13
3
2
1
8
7
6
EM85
EM84
6
6
5
4
3
2
1
5
4
13
12
11
10
9
8
12
11
20
19
18
17
16
10
9
3. Make sure meter is in appropriate setting (DC or AC). Using an approved probe
adapter, back probe the correct pin to monitor the signal on the DVOM. Record the
displayed values at the given engine speeds and note the signal voltage type (DC or AC).
Table 1:
Component
Reading @ Idle
Reading @ 2000
RPM
Reading @ 3000
RPM
MAFS =
CMPS (A) =
CMPS (B) =
ECTS =
EOTS =
IATS =
PPS1 =
PPS2 =
TPS1 =
TPS2 =
Instructor Check: _______________________
Student Workbook
880 Worksheet.fm
z
Service Training
Evaporative System Leak Testing
Refer to TSB 05.1.29 This bulletin was issued for the 1996/97 MY Sedan vehicles.
The procedure is valid for all Jaguar vehicles including current production.
Note: The S-TYPE fuel cap is of a different design than all other Jaguar models and requires
a unique filler cap adapter. (Ask your instructor for further information)
Customer Complaint = Check engine light on! Technician has connected connect PDU
to vehicle and checked logged DTC(s). A DTC for a small evaporative system leak was
logged.
1. Reference the DTC summary guide. What is the specific DTC for the vehicle you are currently working on? _____________.
2. List the probable causes for this logged DTC. _____________________________________
_____________________________________________________________________________
3. Follow the procedure as directed in TSB 05.1.29. Note progress and self recognized
tips to help you perform this procedure easier at the dealership.
Instructor Check:
Student Workbook
880 Worksheet.fm
AJ26 N/A ENGINE MANAGEMENT, PART 1 – 1998 MY XK8
VARIABLE
VALVE TIMING
SOLENOID VALVES
ECM AND TCM
COOLING FAN
WY
55
E
EM64-2
MASS
AIR FLOW
SENSOR
B
A
B
EVAPORATIVE
EMISSION
CONTROL
VALVE
CAMSHAFT CRANKSHAFT
POSITION
POSITION
SENSOR
SENSOR
ENGINE
COOLANT
TEMP.
SENSOR
KNOCK
SENSORS
IATS
A
CANISTER
CLOSE
VALVE
B
DOWNSTREAM
OXYGEN SENSORS
FUEL TANK
PRESSURE
SENSOR
A
B
B
A
EM64-1
υ
υ
B
UPSTREAM
HEATED OXYGEN SENSORS
λ
λ
λ
λ
E
E
B+
O
03.1
D
EM10-6
K
19.1
D
EM10-12
O
19.1
I
EM12-12
I
EM12-13
I
EM12-14
I
EM12-15
I
EM12-16
I
EM12-17
O
D
EM12-18
O
EM12-19
EMS CONTROL RELAY
(CIRCUIT CONTINUED)
SECURITY
ACKNOWLEDGE
CAN
G
05.1
EM12-22
PK
O
EM10-16
Y
03.1
D
EM10-17
G
19.1
C–
EM10-25
CAN
19.1
CAN
19.1
Y
C+
EM10-26
G
C–
Y
19.1
EM13-4
O
EM13-11
O
EM13-12
O
EM13-13
I
EM13-17
I
EM13-18
I
EM13-19
I
EM13-20
I
EM13-27
I
EM13-28
EM13-29
P
19.1
D
EM11-3
ENGINE CRANK
GO
03.1
I
EM11-6
ECM PROGRAMMING
W
19.1
D
EM13-2
GY
EM16
78
53
NG
3
GY
GY
EMS20
WP
1
B+
EM14-1
5
2
E
OK
PW
RW
PY
N
S
Y
B
BG
P
O
B+
EM14-2
GR
O
EM13-14
I
EM14-4
EMS3
PI1 -50 -49
O
EM14-5
O
EM14-6
I
EM14-7
I
EM14-8
I
EM14-9
I
EM14-10
O
EM14-11
O
EM14-12
O
EM15-1
O
EM15-2
O
EM15-3
O
EM15-8
O
EM15-9
I
EM15-11
I
EM15-12
I
EM15-22
R
G
-14
-12
R
G
PI2-6
42
EMS19
PS
PU
PN
RG
RY
B
B
B
E
EL2-2
EL3-2
1
2
EL2-1
EL3-1
PI33
-2
BK
EMS38
EM1BR
(EM2BR)
B
EMS37
EM1AL
(EM2AL)
B
EMS36
EM1AR
(EM2AR)
EL1-2
EL1-3
PI33
-1
PI42
-5
PI42
-3
PI42
-1
PI42
-4
PI42
-2
PI6 -3
-4 -1
-2
VACUUM
SWITCHING
VALVES
3
EL4 -1
EL1-5
PW
RW
PY
EMS31
ELS1 – LHD COUPE AND
RHD CONVERTIBLE ONLY.
PEDAL
POSITION
-2
ELS1
THROTTLE MOTOR
POWER RELAY
-1
43
E
EMS18
PI1 -3 -4
PIS9
PI2-7
EL1-4
ENGINE CONTROL
MODULE
(CONTINUED FIG 04.2)
-51
EMS9
BK
R
R
B
B
B
B
G
G
W
-16
UR
EM2 -17
WG
BRD
N
BRD
U
BG
RG
UW
WU
OK
WP
U
W
U
B
W
B
BRD
PS
BRD
C+
EM10-28
ECM PROGRAMMING
U
EMS8
O
EM10-27
CAN
UP
GY
G
R
N
U
BY
BY
BP
I
EM10-15
01.1
B
UW
EM10-13
PARK, NEUTRAL
(CIRCUIT CONTINUED)
RH1-8
G
EM10-14
RH1-9
RH1-10
EM1-10
EMS1
I
PARKING BRAKE
SWITCH
O.K. TO START
EM11-16
EM1-4
UW
UW
BG
EM2-13
EM11-15
I
BG
RG
UW
EM1-9
U
OU
FC19
EM11-14
I
PIS1
BRD
OU
EM1-8 EM10-10
OK
EM11-13
I
-1
II
BT2 -4 -5 -3
BG
FCS35
US
PI1-6
UW
US
NOT
USED
14
BG
BG
BG
B
US
UY
EM11-12
I
N
EM11-11
O
EM24 -2
E
LF40-5
BY
AC13-3
PI1 -5
BRD
EM11-10
I
-20
R
US
BRAKE SWITCH
(RHD)
S
EM11-9
I
BRD
I
PI1 -19
EMS2
RG
UW
UY
G
U
BG
BY
BG
R
K
-1
44
E
K
BRD
ACS16
-18
B
US
AC24-1
PI1 -17
B
GB
AC24-4
P
EM11-8
Y
O
PI1 -22 -23 -21
BRD
EM11-7
O
I
BG
BG
PI1 -25 -26 -24
B
BRD
EM10-23
-57
UP
EM10-22
I
BY
BY
GY
EM10-21
I
-31
B
II
O
BG
UW
B
BK
AC26-1
B
WO
7
EM10-20
WR
AC26-4
US
O
WR
II
GB
B
WO
6
PI1 -56 -54 -52
B+
EM22 -2
-2
51
E
EM14-3
BRAKE SWITCH
(LHD)
-4 -1
50
BG
WR
E
EM23 -3
BT5 -1 -2 -3
-2
E
EM10-9
40
-2
G
R
N
BRD
S
BRD
P
Y
BRD
46
O
PIS10
49
48
-4 -1
LF52 -1
BG
RG
UW
E
NO
74
PI1-27
47
BY
BY
PI1-16
B+
EM10-5
B
BRD
EM10-1
II
W
B
EM21 -3
-2
WP
-2 PI27 -1
U
W
R
W
-2 PI26 -1
-1
BRD
PU
-3
R
W
S
W
-2 PI17 -1
PI15 -1
PI4 -2
BG
B+
-3
-4
S
WP
WU
PI35 -5 -2 -1
UY
WK
E
-1
UP
36
EM58 -2
BG
WR
-2
BY
GY
WU
39
PI32 -1
-2
WU
RY
PI31 -1
RG
EM2AL
(EMIAL)
PN
EMS43
EM2AR
(EM1AR)
THROTTLE
MOTOR
MECHANICAL
GUARD
PEDAL POSITION AND
MECHANICAL GUARD SENSORS
THROTTLE POSITION
SENSOR
THROTTLE ASSEMBLY
08.1
NOT
USED
AJ26 N/A ENGINE MANAGEMENT, PART 2 – 1998 MY XK8
II
SR
RH1-11
B
-1
PI24-2
-1
PI21-2
-1
PI22-2
-1
PI19-2
-1
PI20-2
-1
PI25-2
PW
-1
PI23-2
680 Ω
KN
FUEL PUMP
-1
PI18-2
AC24-3
BRAKE CANCEL
SWITCH (RHD)
NY
BT55-2
B
12
FC63
-8
ON / OFF
GU
W
WG
FC63
-9
GP
AC24-2
WU
FCS71
PW
BT2-6
WU
AC13-16
4B
560 Ω
GO
WU
PG
3A
PW
WU
ACS22
ACS14
FUEL PUMP RELAY (#4)
560 Ω
FC63
-7
GR
PG
AC26-3
2A
PW
BT11-10
AC26-2
1B
GB
II
SP
WU
PG
KN
4A
PW
BT11-1
FC63
-10
GW
10.2
PW
2
DIMMER OVERRIDE
GK
1
#7 20A
26
BRAKE CANCEL
SWITCH (LHD)
NY
3B
PW
5
GS
3
2B
1A
RLG
PW
1
IGNITION COILS
CRUISE CONTROL SWITCH
TRUNK FUSE BOX
AC13-15
EM3-2
SR
SW1
-4
SC3-4
BT55-1
DECEL
SR
CASSETTE
SW2-4
430 Ω
SW3-3
BO
SW3-4
PW
SET / ACCEL
KN
FUEL TANK
PG
WU
SP
PIS5
680 Ω
PW
PI1-53
BT2AL
SG
SG
EM2-9
EM12-9
O
EM12-10
O
EM13-1
O
EM13-3
O
EM13-15
O
EM13-16
O
EM13-22
O
EM13-23
O
EM13-24
O
EM13-25
O
EM13-26
O
EM13-31
O
EM13-32
O
EM13-33
O
EM13-34
O
EM15-4
O
EM15-5
O
EM15-6
O
EM15-7
O
EM15-15
O
EM15-16
O
EM15-17
O
EM15-18
BO
BO
BO
SW1
-6
SC3-12
FCS48
CASSETTE
CRUISE CONTROL SWITCHES
SW2-6
STEERING WHEEL
BK
SR
WU
SG
EM27
-8
EM27
-7
EM27
-12
EM27
-11
EM27
-10
EM29
-8
EM29
-11
GP
EM12-8
I
PW
PW
EM29
-7
EM29
-12
PW
5
3
NW
UB
2
1
WP
CIRCUITS THAT MUST REMAIN SEPARATE. DO NOT CONNECT OR
CROSS-SWITCH THE BO AND BK CIRCUITS.
52
E
IGNITION COIL
RELAY
CAUTION!: THE STEERING WHEEL CONTAINS TWO LOGIC GROUND
FC3BL
81
EMS22
EM29
-10
IGNITION
MODULE 1
1A
WU
YW
SLG
SG
RY
EM27
-1
EM27
-2
2B
EM27
-3
3B
EM27
-6
4A
1B
EM27 EM27
-5
-9
EM29
-9
EM29
-1
EM29
-2
2A
EM29
-5
3A
EM29
-3
IGNITION
MODULE 2
4B
EM29
-6
EM1-13
KN
SP
W
WU
UB
LGK
LGO
LGW
LGU
LGY
LGR
LGS
LGP
EM2-12
EM1-3
LGY
I
PI1-43
GO
EM12-6
PI1-44
LGO
EM12-5
I
PI1-45
LGW
I
PI1-46
GR
EM11-5
PI1-39
LGP
I
PI1-41
GB
EM11-4
PI1-42
B
I
EM26
PI1-40
GW
EM11-1
SWS1
RESUME
B
I
BO
SW3-2
GK
EM10-11
430 Ω
SW3-1
LGK
EM10-4
I
CASSETTE
SW2-3
LGR
I
UG
ULG
UN
PG
CANCEL
SG
SW1
-3
SC3-3
GS
EM10-3
EM3-1
LGS
I
EM3-4
LGU
EM10-2
EM3-3
GU
O
EM3-6
EM2-14
RLG
UG
ULG
UN
UB
RLG
AC13-9
AC12-19
AC12-12
AC12-14
EM2-6
EMS31
UG
ULG
UN
UB
RLG
I
AC3-1
O
AC4-9
O
AC4-17
I
AC1-1
I
AC12-13
NOTE: REFER TO FIGURES 07.1
AND 07.2 FOR COMPLETE A/C
CIRCUITS.
EM2AR
(EM1AR)
AC4-7
AIR CONDITIONING
CONTROL MODULE
EM17
RLG
5
3
NLG
RY
2
1
WP
77
EMS26
54
E
BO
BY
BW
BU
BP
BG
BN
BS
AIR CONDITIONING
COMPRESSOR CLUTCH RELAY
OG
LF9-2
W
W
WU
LF9-9
LF40-6
PI1-30
PI1-32
PI1-33
PI1-34
PI1-35
PI1-36
PI1-37
RLG
RLG
PI1-13
OY
PI1-38
ENGINE CONTROL
MODULE
45
E
LF9-8
NG
LF9-3
LF9-5
B
PI36-1
AIR CONDITIONING
COMPRESSOR
CLUTCH
70
WU
WU
LF9-7
LF40-7
EM5
76
NY
3
5
BR
37
WK
1
2
B
BR
PI2-5
PIS2
P
LF9-1
B
II
PI7-2
BP
BR
BO
BR
BY
BR
BS
BR
BW
BR
BG
BR
BN
BR
BU
-1
PI8-2
-1
PI9-2
-1
PI10-2
-1
PI11-2
-1
PI12-2
-1
PI13-2
-1
PI14-2
YW
NLG
-1
LF12-1
LF12-2
RH RADIATOR FAN
B
OY
LF13-2
NOTE: ECM POWER SUPPLIES AND GROUNDS SHOWN ON FIG 04.1.
1A
2A
3A
4A
1B
FUEL INJECTORS
2B
3B
4B
LF13-1
LH RADIATOR FAN
LF2AL
69
WU
LF57-1
YW
YW
LF40-11
OG
LF57-5
LF40-9
RADIATOR FAN CONTROL
RELAY MODULE
UB
WU
WU
BR
EM2AR
(EM1AR)
LF3-6
LF2AR
B
FUEL INJECTION
RELAY
UB
UB
EMS31
2–30 BAR
12 BAR
BK
BK
LF57-2
20 BAR
BK
BK
LF57-4
LF57-3
REFRIGERANT
4-WAY PRESSURE
SWITCH
LFS25
BK
LF2BL
AJ26 SC ENGINE MANAGEMENT, PART 1 – 1999 MY XKR
HO2S
ECM AND TCM
COOLING FAN
EVAPP
MAFS
CMPS
IATS
WY
60
KS
KS
CKPS
ECTS
EM64-2
EM64-1
IATS2
B
B
A
B
E
HO2S
A
υ
υ
λ
υ
λ
NOT
USED
NOT USED
B
NOT
USED
EM10-5
NO
79
EM10-9
WR
43
E
II
GB
B
WO
6
AC24-4
US
AC24-1
EM11-7
B+
EM14-3
US
AC13-3
US
FCS35
US
I
O
EM11-8
I
EM11-9
I
EM11-10
I
EM11-11
O
EM11-12
I
EM11-13
EM1-8 EM10-10
EM11-14
BRAKE SWITCH
I
EM11-15
I
EM11-16
PI1-6
EM1-9
UW
EM1-4
-20
PI1 -5
BG
BG
BG
BG
RG
UW
PIS1
BG
BG
RG
UW
RH1-9
RH1-10
EM1-10
EMS1
E
BT2-4
BT2-5
BT2-3
RH1-8
UW
EM10-14
EM12-2
EM12-3
PARKING BRAKE
SWITCH
EM12-4
EM12-14
I
EM12-15
EM10-12
EM12-16
SECURITY
ACKNOWLEDGE
EM12-19
EM10-15
PK
EM12-22
Y
03.2
D
EM10-17
19.1
CAN
19.1
CAN
19.1
G
C–
EM10-25
Y
C+
EM10-26
G
C–
EM10-27
Y
19.1
EMS8
O
EM10-16
CAN
CAN
EM12-18
O
C+
O
EM13-4
O
EM13-11
O
EM13-12
O
EM13-13
I
EM13-17
I
EM13-18
I
EM13-19
I
EM13-20
I
EM13-27
I
EM13-28
EM10-28
ECM PROGRAMMING
P
19.1
EM13-29
D
EM11-3
ENGINE CRANK
GO
03.2
I
EM11-6
ECM PROGRAMMING
W
19.1
D
EM13-2
GY
EM16
82
55
NG
3
GY
GY
EMS20
WP
1
2
E
EM14-4
O
EM14-5
O
EM14-6
I
EM14-7
I
EM14-8
I
EM14-9
I
EM14-10
O
EM14-11
O
EM14-12
O
EM15-1
O
EM15-2
O
EM15-3
I
EM15-11
I
EM15-12
I
EM15-22
OK
EM3-7
BRD
RH2-18
EMS3
PI1 -50 -49
-51
-14
-12
PI1 -3 -4
-1
PIS9
EMS9
R
G
BK
R
R
B
B
B
B
G
G
44
EMS19
R
G
PI2-7
45
E
EL2-2
EL3-2
1
2
PI42
-3
PI42
-1
PI2-6
E
PI33
-2
PI33
-1
PI42
-5
PI42
-4
PI42
-2
PI6 -3
-4 -1
-2
VACUUM
SWITCHING
VALVES
3
EMS18
H
H
TPS/1
TPS/2
B+
EM14-1
5
I
OK
OK
PW
RW
PY
N
S
Y
B
BG
P
O
G
01.1
I
UW
BG
EMS CONTROL RELAY
(CIRCUIT CONTINUED)
G
UW
05.2
O
U
EM10-13
PARK, NEUTRAL
(CIRCUIT CONTINUED)
EM12-17
D
BRD
O
19.1
B+
EM14-2
GR
O
EM13-14
PS
PU
PN
B
B
B
PPS/1
EL2-1
EL4 -1
-2
ELS1
EL1-4
EL1-2
THROTTLE MOTOR
POWER RELAY
ENGINE CONTROL
MODULE
EL3-1
B
BG
D
UW
K
19.1
EM12-13
I
BK
EMS38
EM1BR
(EM2BR)
B
EMS37
EM1AL
(EM2AL)
B
EMS36
EM1AR
(EM2AR)
EL1-3
PW
RW
PY
B
I
BY
D
EM10-6
EM12-12
R
O
03.2
EM12-7
I
THROTTLE
MOTOR
PPS/2
MECHANICAL
GUARD
PEDAL POSITION AND
MECHANICAL GUARD SENSORS
THROTTLE
POSITION SENSOR
EL1-5
B
O.K. TO START
I
YU
YG
YN
YR
UP
UP
GY
G
R
N
U
BY
BY
BP
EMS31
B
EM2-13
EM12-1
WR
FC19
I
K
BRD
OU
WR
OU
EM2AR
(EM1AR)
ELS1: CRUISE CONTROL
VEHICLES ONLY.
-1
UP
BG
-1
BRD
U
BRD
EM24 -2
N
BG
RG
UW
WU
50
E
-1
PI3 -2
PI1 -15
UP
PI1 -19
EM22 -2
BG
RG
UW
-18
NOT
USED
FT2 -1 -2 -3
FT1 -2 -1 -3
BT1-6
53
OK
PI1 -17
UY
PI1 -22 -23 -21
OK
-2
-2
WP
-4 -1
BRD
PS
G
52
B
W
B
U
B
WP
UY
R
N
BRD
S
BRD
P
Y
BRD
O
B
BRD
PI1 -25 -26 -24
N
PN
EMS2
RG
UW
UY
G
U
BG
BY
BG
R
K
-57
BRD
EM10-23
BG
BG
BG
B+
-31
S
I
PI1 -56 -54 -52
BRD
EM10-22
EM23 -3
-2
E
P
I
BG
UW
B
BK
E
Y
EM10-21
47
BRD
II
B+
EM10-20
O
E
O
WK
39
O
51
UP
B+
EM10-1
E
-4 -1
BT14 -1
BY
BY
GY
E
YU
YG
YN
YR
WR
42
E
59
BY
BY
LF3 -8
58
B
BRD
PI1 -8 -9 -10 -7
W
B
EM21 -3
-2
PIS10
BRD
PU
-2 PI27 -1
-1
U
W
R
W
-1 PI26 -1
PI4 -2
BG
-1 PI17 -2
PI15 -2
R
W
S
W
S
-3
-4
UP
PI35 -5 -2 -1
BG
-1
BY
GY
WU
LF58 -2
WP
-5
-2
WP
YU
YG
YN
YR
-4 -1 -6 -3
WP
PI34
EM2AL
(EMIAL)
PN
EMS43
THROTTLE ASSEMBLY
AJ26 SC ENGINE MANAGEMENT, PART 2 – 1999 MY XKR
IGNITION COILS
2
SR
BT11-10
TRUNK FUSE BOX
I
EM11-5
I
EM12-5
I
EM12-6
I
EM12-8
I
EM12-9
O
EM12-10
O
EM13-1
O
EM13-3
SW2-4
2
1
WP
85
54
PW
PW
GP
IGNITION COIL
RELAY
CASSETTE
SW3-4
PW
SET ACCEL
PIS5
680 Ω
KW
EM3
-6
RH2
-15
EM3
-3
EM3
-4
SG
SG
EM3-1
CANCEL
SG
SW1
-3
SC3-3
SW2-3
CASSETTE
BO
430 Ω
SW3-1
SW3-2
SWS1
EM31
PI1-40
PI1-42
PI1-41
PI1-39
PI1-46
PI1-45
PI1-44
PI1-43
PW
PW
SC3-12
SW2-6
CASSETTE
KW
STEERING WHEEL
BK
FC3BL
EM2
-9
EM2
-15
CAUTION!: THE STEERING WHEEL CONTAINS TWO LOGIC GROUND
CIRCUITS THAT MUST REMAIN SEPARATE. DO NOT CONNECT OR
CROSS-SWITCH THE BO AND BK CIRCUITS.
EM27
-8
EM27
-7
IGNITION
MODULE 1
EM27
-12
1A
EM27
-1
EM27
-2
2B
EM27
-3
EM27
-11
3B
EM29
-8
EM29
-11
4A
EM29
-7
1B
EM27 EM27
-5
-9
EM27
-6
EM27
-10
EM29
-9
EM29
-1
GP
SW1
-6
FCS48
KN
BO
GO
BO
BO
WU
YW
SLG
SG
RY
UB
PI1-53
BO
430 Ω
SW3-3
RESUME
SR
WU
SG
NW
EMS22
EM29
-2
EM29
-12
2A
EM29
-5
3A
EM29
-3
WB
5
3
RY
1
2
NW
75
B
EM29
-10
4B
INTERCOOLER
PUMP RELAY
IGNITION
MODULE 2
B
WB
EM29
-6
EM75-2
LGY
EM11-4
-1
PI25-2
LGO
EM11-1
I
-1
PI20-2
LGW
I
-1
GR
EM10-11
PI19-2
LGP
I
-1
PI22-2
GB
EM10-4
-1
GW
I
SP
DECEL
SR
SW1
-4
SC3-4
GK
EM10-3
PI21-2
LGK
I
-1
PI24-2
LGR
EM10-2
SR
EM3-2
LGU
O
KN
RH1
-11
UG
ULG
UN
PG
PG WU
BT2
-15
BT2
-6
FUEL PUMP 1 RELAY (#4)
3
680 Ω
KN
II
-1
PW
NY
PI23-2
GS
1
28
-1
PI18-2
BT11-1
#7 20A
5
E
GO
ON / OFF
GU
5
EM26
PW
II
GU
3
4B
12
FC63
-8
BRAKE CANCEL
SWITCH
1
3A
PW
AC13-16
WG
FC63
-9
GR
WU
FCS71
2A
PW
AC13-15
WU
AC24-3
GB
WU
AC24-2
FC63
-7
PW
PG
1B
510 Ω
GW
PG
KW
4A
PW
2
II
270 Ω
GK
SP
UW
LGS
1
WG
24
5
FC63
-10
PW
3
NW
68
10.2
3B
PW
DIMMER OVERRIDE
BT51
2B
1A
RLG
GS
FUEL PUMP 2 RELAY
EM75-1
INTERCOOLER
PUMP
B
B
EM13-16
O
EM13-22
O
EM13-23
O
EM13-24
O
EM13-25
O
EM13-26
O
EM13-31
O
EM13-32
O
EM13-33
O
EM13-34
O
EM15-4
O
EM15-5
O
EM15-6
O
EM15-7
O
EM15-15
O
EM15-16
O
EM15-17
O
EM15-18
LF40-6
LF40-7
EM1-13
EM2-12
EM1-3
W
PI1-32
PI1-33
BN
BU
BR
BR
PI1-34
PI1-35
PI1-36
PI1-37
PI1-38
WU
LF9-5
LF9-3
OY
NG
I
AIR CONDITIONING
CONTROL MODULE
5
3
NLG
RY
2
1
WP
81
56
E
AIR CONDITIONING
71
B
RLG
PI36-1
LF9-1
AIR CONDITIONING
COMPRESSOR
CLUTCH
BR
IJS1
LF2AR
IJ2-5
BP
IJ2-4
BR
IJ2-3
BO
IJ2-2
BR
IJ1-5
BY
IJ1-4
BR
BR
IJ1-3
BS
IJ1-2
EM2AR
(EM1AR)
BR
BR
P
RELAY MODULE
NLG
IJ3-2
-1
IJ4-2
-1
IJ5-2
-1
IJ6-2
-1
IJ7-2
-1
IJ8-2
-1
IJ9-2
-1
IJ10-2
-1
LF12-1
BTS50
LF12-2
LF13-2
BT2AL
1A
2A
3A
4A
1B
FUEL INJECTORS
2B
3B
4B
LF2AL
WU
LF57-1
YW
LF40-11
LF13-1
LH RADIATOR FAN
LF57-5
WU
WU
YW
B
OY
LF3-6
LF40-9
RH RADIATOR FAN
B
70
UB
UB
UB
FT1-10
NOTE: ECM POWER SUPPLIES AND
GROUNDS SHOWN ON FIG 04.4.
I
AC1-1
RLG
PI1-13
OG
FUEL TANK
O
AC4-17
E
RLG
BW
EMS31
FUEL INJECTION
RELAY
FT1-8
LF9-8
B
B
B
IJ1-1
FT1-5
B
AC4-9
WU
IJS2
BR
2
IJ2-1
BG
1
LF9-9
46
BR
BR
WK
II
BR
PIS2
PI2-5
40
FUEL
PUMP 2
FT3-3
O
LF9-7
5
BN
3
BR
NY
BU
80
UW
FT3-4
AC12-14
I
AC3-1
EMS26
LF9-2
B
FT3-1
AC12-12
AC4-7
EM17
EM5
FUEL
PUMP 1
AC12-19
UG
ULG
UN
UB
RLG
AC12-13
OG
PI1-30
FT1-4
AC13-9
CIRCUITS.
ENGINE CONTROL
MODULE
FT3-2
UG
ULG
UN
UB
RLG
EM2-6
BO
BY
BW
BU
BP
BG
BN
BS
NY
EM2-14
RLG
BP
O
EM2AR
(EM1AR)
W
WU
BO
EM13-15
BY
O
KW
RY
W
WU
UB
LGK
LGO
LGW
LGU
LGY
LGR
LGS
LGP
BS
EM13-10
BW
EM13-9
O
B
BG
O
EMS31
KN
SP
YW
2–30 BAR
BK
BK
LF57-2
20 BAR
LF2BL
12 BAR
BK
RG
LF57-4
LF57-3
REFRIGERANT
4-WAY PRESSURE
SWITCH
9
II
AJ27 N/A ENGINE MANAGEMENT, PART 1 – 2001 MY XJ8
ECM AND TCM
COOLING FAN
VVT
EVAPP SOLENOID VALVES***
W
U
EM66-2
EM66-1
WR
52
I
I
EM82-12
O
EM81-03
I
EM81-07
I
EM81-09
I
EM81-10
I
EM81-16
I
EM81-18
I
EM81-19
EM81-24
EM82-01
D
EM82-16
I
EM82-04
I
EM82-05
EM82-07
I
EM81-12
EM82-10
EM82-11
C–
EM82-14
C–
I
EM82-17
C+
O
EM83-03
EM83-05
EM83-06
EM83-25
EM83-07
D
I
EM80-17
21.2
ECM PROGRAMMING
21.2
ECM PROGRAMMING
21.2
W
EM83-12
EM80-18
EM83-13
I
D
I
EM83-18
I
EM83-19
I
EM83-21
I
EM83-22
I
EM83-23
EM83-17
EM80-27
GW
EM49
NG
84
3
GW
GW
EMS20
WU
59
1
B+
EM80-08
5
2
B+
EM80-09
GR
E
EM83-14
D
EM80-19
U
EM83-08
EM83-09
D
W
EM83-26
EM83-27
O
EM82-06
BW
-31
EM8L
B
EMS38
EM16R
B
EMS37
EM16L
3
NG
B
2
1
WU
EM80-31
EM85-07
EM81-08
EM84-01
EM84-16
EM84-22
85
62
OY
R
N*
BG
Y
G*
UY
O
O2S HEATERS
RELAY
B
EM16L
I
EM83-28
O
EM84-07
O
EM84-15
RU
OY
BG
P
Y
N
BR
BG
N*
O
B
G
N*
N
N
BW
BW
GW
OY
EMS1
BG
BG
BG
BG
PIS1
PI1-6
EMS2
BG
EM3 -9
-12 -8
EMS3
FC1 -34 -30 -35
PI1 -50 -49
EM85-02
I
I
EM85-08
BT4 -35 -48 -34
56
E
I
NOTES:
I
* EARLY PRODUCTION VEHICLES HAVE
WIRE COLOR CODES THAT ARE DIFFERENT
FROM THAT SHOWN. USE CONNECTOR
PIN NUMBERS FOR WIRE IDENTIFICATION.
I
I
I
CV1 -2
BT5 -3
-2
-1
FP1 -3
-2
** CCV, FTPS AND ASSOCIATED
WIRING – NAS VEHICLES ONLY.
I
ENGINE CONTROL
MODULE
-1
PI2-7
PI2-6
PIS9
PI2-11
PI29
-3
I
-3 -4
PI1 -14
E
G
O
CV2-3
R
I
FC1-45
WU
EM85-01
EM2-18
PI2-13
RU
O
RU
UY
WG
55
O
BK
I
O
OY
RG
BG
GU
-51
W
OY
RG
BG
U
UY
-1
PI29
-1
PI29
-2
PI33
-1
PI33
-2
PI42
-4
PI42 PI42 PI42
-2
-1
-3
PI6
-4
PI6
-3
PI6
-2
PI6
-1
BK
OY
RG
BG
EM80-21
WG
5
E
WU
EM80-03
W
UY
WG
EMS37
O
EM81-21
N
Y*
W
EM75
I
EM80-29
WG
Y*
U
N*
EMS8
W
W
OY
RW
OG
RG
B*
N*
RG
O*
G
BG
-1
EMS36
BK
*** VVT AND ASSOCIATED WIRING –
NOT FITTED TO 3.2 L ENGINES.
EMS36
WG
-57
EMS9
EM85-06
BK
G*
UY
N*
WG
Y
RU
O
R
-52
R
THROTTLE MOTOR
POWER RELAY
BK
BK
B
B
B
B
B
B
B
B
B
-2
G
C+
O
-3 -1
W
Y
EM24 -4
W
Y
-2
OY
G
I
EM83-24
-3 -1
W
21.2
EM22 -4
W
-2
OY
RG
BG
21.1
BG
WU
GW
BW
BG
BG
YG
W
W
N
N*
W
O
B
W
N
G
P
BW
-56
OY
RG
BG
CAN
-4 -1
E
EM83-16
21.1
EM23 -3
BG
G
EM83-15
CAN
-2
OY
RU
21.1
-4 -1
EM21 -3
EMS46
EM82-15
CAN
-4
O
EM81-06
O
-5
54
BG
EM81-02
O
-1
GW
O
-3
PIS10
PI1 -54
YG
EM81-01
W
UY
O
PI35 -2
PI2 -9
UY
EM80-15
Y*
W
PI1 -5
PI1 -19
W
EM80-07
I
W
W
-18
N
O
EMS19
PI1 -17
Y*
EM80-06
PI1 -25 -26 -24
N*
O
EMS18
-2
O
EM80-05
-3
B
W
EM80-04
O
PI2 -1
N
O
PI1 -22 -23 -21
G
W
EM80-02
-2
E
P
O
UY
GU
G
G
R
R
YG
Y
EM80-01
-1 PI38 -1
-2
D
Y
03.1
-2 PI27 -1
BG
W
03.1
21.1
-1 PI26 -1
G
GO
03.1
CAN
PI1
-27
-2 PI15 -2
W
U
01.1
05.1
PI2
-10
PI4 -2
PI16 -1
O*
II
PARK, NEUTRAL
(CIRCUIT CONTINUED)
λ
N*
GU
6
O
EM82-02
SECURITY
ACKNOWLEDGE
λ
U
I
EM81-22
PARKING BRAKE
SWITCH
O.K. TO START
B
OY
OY
EM53-11
ENGINE CRANK
PI1
-16
-1
BW
OG
EMS21 EM82-08
EM1-1
CC11-1
EMS CONTROL RELAY
(CIRCUIT CONTINUED)
PI2
-8
PI17 -2
BW
OG
OY
APPLIED ONLY WHEN THE INERTIA
SWITCH IS ACTIVATED
U
υ
A
N
OG
LFS1
LF3-1
B
B*
CAS81
EMS21: ADAPTIVE DAMPING ONLY.
OG
-2
Y
57
CC40-1
OG
-2 PI32 -1
W
B+
EM83-20
OG
PI31 -1
W
NR
80
CA19-16
-1
EM82-09
CC40-4
BRAKE SWITCH
A
IATS
υ
HO2S
DOWNSTREAM
HO2S
UPSTREAM
MAFS
B
W
II
EM39 -2
RG
B+
OG
W
RW
B+
EM82-13
46
OG
A
υ
OY
WR
E
WU
B
EOTS
ECTS
EM81-17
53
II
CMPS
A
KS
B+
E
11
KS
EM85-05
WU
E
CMPS
B
A
O
UY
63
CKPS
SHIELDING SHOWN AS DASHED
LINES ARE BRAIDED WIRES.
EM8L
BRD
CCV**
FTPS**
AIR ASSIST
CLOSE VALVE
THROTTLE
MOTOR
PPS/1
PPS/2
TPS/1
TPS/2
THROTTLE ASSEMBLY
AJ27 N/A ENGINE MANAGEMENT, PART 2 – 2001 MY XJ8
EM52
RG
5
3
NG
RW
2
1
WU
83
EMS26
RG
EM53-10
EM53-9
EM53-8
EM53-3
U
CC28-01
I
CC31-09
O
CC31-07
I
CC30-01
O
CC31-17
I
EM53-12
NG
72
OY
CF1-2
OY
CF1-1
LH RADIATOR FAN
W
W
WU
LF31-9
2
B
A/CCM
WR
II
BT11-10
RW
EM51-10
EM80-12
I
EM80-20
I
EM80-22
I
EM80-23
O
EM80-25
O
EM81-04
O
EM81-05
I
EM81-13
I
EM81-14
I
EM81-15
O
EM83-04
I
EM83-10
I
EM83-11
O
EM84-02
O
EM84-03
O
EM84-04
O
EM84-05
O
EM84-06
O
EM84-09
O
EM84-10
O
EM84-11
O
EM84-12
O
EM84-13
O
EM84-14
O
EM84-17
O
EM84-18
O
EM84-19
O
EM84-20
O
EM84-21
W
RG
CIRCUITS.
WU
7
REFRIGERANT
4-WAY PRESSURE SWITCH
II
680 Ω
YR
CC40-2
EM53-17
CCS21
CC40-3
DECEL
YR
SW1
-4
WU
U
CASSETTE
SW2-4
BO
430 Ω
SW3-3
SW3-4
SET / ACCEL
BRAKE CANCEL
SWITCH
680 Ω
SC3-4
YG
EM3
-5
CANCEL
YG
SW1
-3
SC3-3
CASSETTE
SW2-3
BO
430 Ω
SW3-1
SW3-2
WU
YR
YG
PI1-2
PIS11
YG
YG
PI1-29
BO
WU
EM53-16
YR
YG
EM3-11
BK
BG
BO
BW
BW
BW
GW
GO
GR
GU
BR
BG
GU
GO
GW
GB
BO
PIS12
FCS28
BO
SC3-12
BO
SW1
-6
CASSETTE
SW2-6
STEERING WHEEL
FC17R
YG
YG
YG
YG
YG
YG
YG
YG
RW
PIS5
PI1-53
EM26
RW
5
3
NW
B
2
1
WU
88
60
E
EMS38
B
EM16R
PI1-40
PI1-42
PI1-41
PI1-39
PI1-46
PI1-45
PI1-44
IGNITION COIL
RELAY
PI1-43
EM25
ENGINE CONTROL
MODULE
81
NW
3
5
BR
BR
PI2-5
47
W
1
2
II
NG
PIS2
B
EMS11
B
GO
YG
RW
B
GU
YG
RW
B
PI1-38
BR
BR
PI1-37
BO
BR
PI1-36
BW
BR
PI1-35
BW
BR
PI1-34
BW
BR
PI1-33
BG
PI1-32
BO
EM17
BR
B
BG
FUEL INJECTION
RELAY
BR
PI1-30
FUEL
PUMP
BR
BT17-6
PI51 -3 -2 -4 -1 PI56 -3 -2 -4 -1 PI57 -3 -2 -4 -1 PI54 -3 -2 -4 -1 PI55 -3 -2 -4 -1 PI52 -3 -2 -4 -1 PI53 -3 -2 -4 -1 PI58 -3 -2 -4 -1
BTS21
PI7-2
-1
PI8-2
-1
PI9-2
-1
PI10-2
-1
PI11-2
-1
PI12-2
-1
PI13-2
-1
PI14-2
-1
B
FUEL TANK
PIS13
PI1-55
BT20
B
EMS4
B
EM8R
1A
SWS1
RESUME
WR
YG
YG
B
11
CC20
-8
ON / OFF
YU
EM53-14
WU
W
WU
YR
YG
DIMMER
OVERRIDE
WG
CC20
-9
RELAY MODULE
LF10R
10.2
CC20
-10
510 Ω
CC20
-7
LF31-1
EM3-10
BT17-5
270 Ω
YU
B
II
LF26-4
LF26-3
WU
UY
U
YU
U
RW
UY
RW
EM80-16
EM1-12
GR
YG
RW
B
O
BK
LF31-7
GW
YG
RW
B
O
12 BAR
WU
GO
YG
RW
B
EM80-11
AIR CONDITIONING
COMPRESSOR CLUTCH
GW
YG
RW
B
EM80-10
73
LF31-3
LF31-5
LF32-4
B
PI36-1
LFS17
LF20L
LF26-1
RW
WR
BK
LF26-2
20 BAR
WU
EM51-5
FC1
-42
I
RG
LF26-5
EM51-6
CF2-2
WU
2–30 BAR
U
WR
WU
I
RG
RH RADIATOR FAN
P
U
TRUNK FUSE BOX
NG
OG
OG
CF2-1
LF10L
BT4
-19
B
LF32-3
GU
YG
RW
B
1
E
PI1-13
BT11-1
#7 20A
33
61
LF31-8
NG
GW
YG
RW
B
1
5
AIR CONDITIONING
LF31-2
LF32-1
EM1-11
3
58
E
RG
UY
U
UY
2A
3A
4A
1B
FUEL INJECTORS
2B
3B
4B
1A
2B
3B
4A
1B
IGNITION COILS
2A
3A
4B
AJ27 SC ENGINE MANAGEMENT, PART 1 – 2001 MY XJR
HO2S UPSTREAM
CMPS
A
W
U
EM66-2
EM66-1
52
WR
53
WR
46
W
CA19-16
CAS81
OG
OG
LFS1
LF3-1
OG
OG
I
EMS21 EM82-08
EM1-1
OY
OY
CC11-1
EM53-11
I
EM81-22
PARKING BRAKE
SWITCH
APPLIED ONLY WHEN THE INERTIA
SWITCH IS ACTIVATED
EMS CONTROL RELAY
(CIRCUIT CONTINUED)
ENGINE CRANK
GU
6
II
I
EM82-12
U
01.1
O
EM81-03
GO
03.2
I
W
03.2
03.2
PARK, NEUTRAL
(CIRCUIT CONTINUED)
05.2
CAN
21.1
EM80-04
EM80-05
O
EM80-06
O
EM80-07
I
EM80-15
I
EM80-28
I
EM81-09
I
EM81-10
I
EM81-16
I
EM81-18
I
EM81-19
I
A
B
λ
U
85
λ
62
E
3
1
5
2
-4
-3 -1
-2
EM75
EM24 -4
WG
-2
W
UY
-3 -1
N
EM22 -4
WG
-2
Y*
U
-4 -1
N*
EM23 -3
WG
R
-2
G*
UY
-4 -1
N*
EM21 -3
WG
-5
Y
RU
-1
O
BW
BW
BG
O
BW
54
E
-56
-52
-31
W
W
-57
O
PI1 -54
BG
UY
PI1 -15
GW
PI1 -5
PI2 -9
O
PI1 -19
W
-18
N
N*
Y*
W
Y*
PI1 -17
-3
PIS10
BW
W
W
O
B
W
PI1 -25 -26 -24
N
-2
YG
UY
GU
G
G
R
R
YG
BW
-3
PI35 -2
BG
-1
WU
PI3 -2
GW
-1
BG
UY
YG
N
PI4 -2
W
N*
W
O
B
N
G
-2
-2
BG
W
-2 PI27 -1
EMS8
Y*
W
B
EMS37
B
WG
EMS9
EMS46
EM16L
EMS18
EMS19
B*
N*
RG
O*
G
O
BG
D
Y
EM82-01
D
EM82-16
RU
I
EM82-04
I
EM82-05
EM82-07
I
EM81-12
G
EM82-10
EM82-11
C–
G
21.1
EM81-23
EM81-24
EM83-15
CAN
EM80-02
O
EM82-15
SECURITY
ACKNOWLEDGE
EM80-01
O
EM82-02
O.K. TO START
U
υ
BW
O
O
OG
-1 PI26 -1
N
EMS21: ADAPTIVE DAMPING ONLY.
PI2 -1
G
W
Y
CC40-1
P
PI1 -22 -23 -21
OG
υ
E
EM83-20
BRAKE SWITCH
W
P
57
B+
CC40-4
Y
EM82-09
W
B+
NR
PI38 -1
-2 PI15 -2
PI16 -1
EM82-13
80
-1
W
PI17 -2
-1
W
EM39 -2
B+
W
OG
υ
B
EM81-17
II
II
A
IATS
υ
O2S HEATERS
RELAY
HO2S DOWNSTREAM
MAFS
B+
E
WU
IATS2
ECTS
B
EM85-05
E
11
A
WU
E
B
EOTS
KS
O
UY
63
KS
CMPS
WU
CKPS
EVAPP
NG
ECM AND TCM
COOLING FAN
C–
I
EM82-14
I
EM82-17
OY
R
N*
BG
Y
G*
UY
O
EM3-12
EM83-16
Y
C+
W
21.2
EM83-09
EM83-12
D
EM80-18
ECM PROGRAMMING
21.2
ECM PROGRAMMING
21.2
W
EM83-13
I
D
I
EM83-18
I
EM83-19
I
EM83-21
I
EM83-22
I
EM83-23
EM80-19
U
EM83-17
EM80-27
GW
EM49
NG
84
3
GW
GW
EMS20
WU
59
1
B+
EM80-08
5
2
B+
EM80-09
GR
E
EM83-14
D
EM83-26
EM83-27
O
EM82-06
I
EM83-28
O
EM84-07
O
EM84-15
OY
BG
EMS2
EM3-8
PIS1
BG
EM3-9
BG
EMS3
PI1-6
EM80-31
EM85-07
EM81-08
EM84-01
EM84-16
EM84-22
O
EM85-03
I
O
EM85-04
I
I
EM85-08
I
O
EM85-09
I
O
EM85-10
PI1-8
EMS36
EM8L
B
EMS38
EM16R
B
EMS37
EM16L
YU
YG
PI1-9
PI1-10
CV2-3
BT4 -34 -48 -35
S1
P134-4
56
E
S2
PI2-7
PI33
-1
PI34-1
YR
YR
PI1-7
I
S3
PI34-6
S4
G
PI2-6
PI33
-2
-3 -4
-1
PIS9
PI42
-4
PI42
-2
PI42
-1
PI42
-3
PI6
-4
PI6
-3
PI6
-2
PI6
-1
BT5 -1 -2 -3
PI34-3
NOTES:
CV1 -2
I
* EARLY PRODUCTION VEHICLES HAVE
WIRE COLOR CODES THAT ARE DIFFERENT
FROM THAT SHOWN. USE CONNECTOR
PIN NUMBERS FOR WIRE IDENTIFICATION.
I
EM85-06
BK
FC1-45
W
EM2-18
B*
I
RU
UY
YU
YG
WG
YR
YR
G
EM85-02
R
EM85-01
O
BG
BW
OY
EM80-21
O
I
-51
BG
RG
OY
EM80-03
I
WU
EM81-21
R
BG
RG
OY
I
EM80-29
PI1 -14
PI1 -50 -49
O
BG
RG
OY
O
O
BK
BK
B
B
B
B
B
B
B
B
B
U
UY
W
FC1 -35 -30 -34
THROTTLE MOTOR
POWER RELAY
BG
EM83-08
G
EM80-17
W
I
W
EM83-07
D
OY
W
EM83-25
O
EMS1
OY
BG
P
Y
N
BR
BG
N*
O
B
G
N*
N
N
BW
BW
GW
N*
EM83-06
OY
21.2
EM83-05
C+
OY
Y
BG
21.1
OY
CAN
O*
EM83-24
W
21.1
BG
RG
OY
CAN
** CCV, FTPS AND ASSOCIATED
WIRING – NAS VEHICLES ONLY.
ENGINE CONTROL
MODULE
SHIELDING SHOWN AS DASHED
LINES ARE BRAIDED WIRES.
BRD
50
WU
51
WU
E
E
-1
FP1 -1 -2 -3
EM10 -1 -2 -3
STEPPER
MOTOR
PI34-2
THROTTLE
MOTOR
PI34-5
EGR VALVE
CCV**
FTPS**
MAPS
PPS/1
PPS/2
TPS/1
TPS/2
THROTTLE ASSEMBLY
AJ27 SC ENGINE MANAGEMENT, PART 2 – 2001 MY XJR
TRUNK FUSE BOX
EM52
1
3
5
O
#15 20A
33
1
BT12-2
2
BT10-5
RG
EM53-10
EM53-9
EM53-8
1
3
5
33
1
EM53-3
NG
2
U
CC28-01
I
CC31-09
O
CC31-07
I
CC30-01
O
CC31-17
I
NG
72
OY
CF1-2
CF1-1
LF30-2
LF31-2
LF32-1
W
W
WU
LF31-9
EM1-11
BT4
-19
WR
B
A/CCM
BT4
-9
EM80-10
I
EM80-11
O
EM80-12
O
EM80-14
O
EM80-16
I
EM80-20
I
EM80-22
I
EM80-23
O
EM80-25
O
EM81-04
O
EM81-05
I
EM81-13
I
EM81-14
I
EM81-15
WU
W
WU
YR
YG
EM82-03
WB
O
WR
WU
UY
U
RW
YU
U
RW
UY
RW
B
2
1
WU
LF10L
WB
LF3
-21
W
EM51-6
WB
2–30 BAR
U
U
WU
LF26-5
20 BAR
WU
RW
CF2-2
EM1-9
E
EM25
73
RG
WB
10
8
NW
RW
6
7
B
B
PI36-1
AIR CONDITIONING
COMPRESSOR CLUTCH
B
WU
WU
LFS17
CIRCUITS.
INTERCOOLER
PUMP RELAY
LF31-7
EM1-12
EM17
WU
RELAY MODULE
YR
YU
WU
U
EM51
-8
CC40-2
EM53-17
CASSETTE
SW2-4
SW3-3
BO
430 Ω
SW3-4
SET / ACCEL
CC40-3
BRAKE CANCEL
SWITCH
DECEL
YR
SW1
-4
EM53-14
CCS21
680 Ω
SC3-4
WU
YR
YG
YG
WU
EM53-16
EM3-11
YR
YG
CANCEL
YG
SW1
-3
SC3-3
CASSETTE
SW2-3
SW3-1
BO
430 Ω
SW3-2
BK
BO
FCS28
BO
BO
SW1
-6
SC3-12
CASSETTE
SW2-6
O
EM84-04
BR
EM25
W
1
2
II
PIS2
B
EMS11
BR
B
B
FUEL INJECTION
RELAY
BT17-3
PI1-36
WU
B
PI1-42
PI1-41
PI1-39
PI1-46
PI1-45
PI1-44
IGNITION COIL
RELAY
PI1-43
BR
IJ1-1
IJS2
IJ1-2
IJ1-3
IJ1-4
IJ1-5
IJ2-2
IJ2-3
IJ2-4
IJ2-5
BR
BT17-2
IJ3-2
FUEL
PUMP 2
-1
IJ4-2
-1
IJ5-2
-1
IJ6-2
-1
IJ7-2
-1
IJ8-2
-1
IJ9-2
-1
IJ10-2
PI51 -3 -2 -4 -1 PI56 -3 -2 -4 -1 PI57 -3 -2 -4 -1 PI54 -3 -2 -4 -1 PI55 -3 -2 -4 -1 PI52 -3 -2 -4 -1 PI53 -3 -2 -4 -1 PI58 -3 -2 -4 -1
-1
B
PIS13
PI1-55
B
BT17-1
B
BTS21
EMS4
B
B
BT20
EM8R
1A
2A
3A
4A
1B
FUEL INJECTORS
2B
3B
4B
1A
2B
3B
4A
1B
IGNITION COILS
2A
3A
4B
88
60
E
EMS38
PI1-37
EM17
O
FUEL TANK
1
BR
PI2-5
47
FUEL
PUMP 1
BR
BO
5
BO
3
PI1-35
2
PI1-38
BR
BT17-4
NW
81
PI1-34
NW
IJS1
BG
NG
PI1-33
BR
IJ2-1
BG
ENGINE CONTROL
MODULE
PI1-32
3
PI1-53
B
PI1-40
PI1-30
5
BR
EM84-21
BR
EM84-20
O
BR
EM84-19
O
BO
EM84-18
O
BO
EM84-17
O
BR
O
BW
EM84-14
BW
EM84-13
O
BR
EM84-12
O
BW
O
PIS5
RW
EM16R
BW
EM84-11
BR
EM84-10
O
BW
O
BW
EM84-09
BR
O
BG
EM84-06
BG
EM84-05
O
BR
O
PIS12
EM26
RW
GW
YG
RW
B
EM84-03
GO
YG
RW
B
O
PI1-29
BG
BO
BW
BW
BW
GW
GO
GR
GU
BR
BG
GU
GO
GW
GB
BO
GW
YG
RW
B
EM84-02
STEERING WHEEL
YG
YG
YG
YG
YG
YG
YG
YG
GU
YG
RW
B
O
PIS11
YG
YG
GO
YG
RW
B
EM83-11
PI1-2
GR
YG
RW
B
I
WR
YG
YG
GW
YG
RW
B
EM83-10
GU
YG
RW
B
EM83-04
SWS1
RESUME
FC17R
I
11
II
CC20
-8
ON / OFF
680 Ω
EM3-10
O
DIMMER
OVERRIDE
WG
CC20
-9
LF20L
LF10R
10.2
CC20
-10
510 Ω
CC20
-7
LF31-1
LF26-3
RG
270 Ω
YU
B
REFRIGERANT
4-WAY PRESSURE SWITCH
EM3
-5
RG
PI1-13
78
EMS11
BK
LF26-2
NG
LF31-3
LF31-5
LF32-4
LF20R
RH RADIATOR FAN
II
12 BAR
RW
EM51-10
58
AIR CONDITIONING
7
LF26-4
BK
LF26-1
EM51-5
83
61
LF31-8
OG
OG
LF32-3 CF2-1
P
FC1
-42
I
RW
LF30-1
INTERCOOLER
PUMP
LH RADIATOR FAN
BT11-10
NG
B
WB
OY
WR
II
3
E
RG
UY
U
UY
EM53-12
BT11-1
#7 20A
5
EMS26
WB
II
RG
INSERT TAB FOR PTEC
ENGINE MANAGEMENT
SECTION HERE
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
POWERTRAIN CONTROL MODULE (PCM)
3
PCM SENSING COMPONENTS – ENGINE
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE VALVE TIMING /
VARIABLE INTAKE
9
EXHAUST GAS RECIRCULATION (EGR):
V6 ONLY
10 OTHER PCM ENGINE CONTROL AND
INTERFACE FUNCTIONS
11 TASK SHEETS
PTEC ENGINE MANAGEMENT SYSTEM
1.2
Student Guide
Service Training
Service Training
Jaguar S-TYPE PTEC Acronyms and Abbreviations
AAI Valve
APP Sensor
B+
CHT Sensor
CKP Sensor
CMP Sensor 1
CMP Sensor 2
DLC
DPFE Sensor
ECT Sensor
EFT Sensor
EGR
EOT Sensor
EVAP Canister Close Valve
EVAP Canister Purge Valve
FTP Sensor
GECM
HO2 Sensor 1 / 1
HO2 Sensor 1 / 2
HO2 Sensor 2 / 1
HO2 Sensor 2 / 2
IAT Sensor
IMT Valve
IP Sensor
KS 1
KS 2
MAF Sensor
NAS
PCM
PSP Switch
PTEC
RECM
ROW
SCP
TACM
TFT Sensor
TP Sensor
VVT Valve 1
VVT Valve 2
Air Assist Injection Valve
Accelerator Pedal Position Sensor
Battery Voltage
Cylinder Head Temperature Sensor
Crankshaft Position Sensor
Camshaft Position Sensor – RH Bank
Camshaft Position Sensor – LH Bank
Data Link Connector
Differential Pressure Feedback EGR Sensor
Engine Coolant Temperature Sensor
Engine Fuel Temperature Sensor
Exhaust Gas Recirculation
Engine Oil Temperature Sensor
Evaporative Emission Canister Close Valve
Evaporative Emission Canister Purge Valve
Fuel Tank Pressure Sensor
General Electronic Control Module
Heated Oxygen Sensor – RH Bank / Upstream
Heated Oxygen Sensor – RH Bank / Downstream
Heated Oxygen Sensor – LH Bank / Upstream
Heated Oxygen Sensor – LH Bank / Downstream
Intake Air Temperature Sensor
Intake Manifold Tuning Valve
Injection Pressure Sensor
Knock Sensor – RH Bank
Knock Sensor – LH Bank
Mass Air Flow Sensor
North America Specification
Powertrain Control Module
Power Steering Pressure Switch
Powertrain Electronic Control
Rear Electronic Control Module
Rest of World Specification
Standard Corporate Protocol Network
Throttle Actuator Control Module
Transmission Fluid Temperature Sensor
Throttle Position Sensor
Variable Valve Timing Valve – RH Bank
Variable Valve Timing Valve – LH Bank
Note the following diagnostic PDU descriptions (refer to CMP Sensors, HO2 Sensors, KS and VVT Valves):
1
Right Hand engine bank (seated in the vehicle)
2
Left Hand engine bank (seated in the vehicle)
/1
Upstream
/2
Downstream
Student Guide
1.3
Service Training
PTEC OVERVIEW
The PTEC (Powertrain Electronic Control) system is a comprehensive combined engine and transmission control system. The system is used on both the 3 liter AJ-V6 and the 4 liter AJ28 V8 engines installed in the Jaguar S-TYPE. There
are detail sensor and control differences between V6 and V8, however the majority of the system is identical in its functions. PTEC complies with OBD II and is capable of achieving future LEV (Low Emission Vehicle) emission standards.
PTEC has several features that are unique from other
Jaguar engine management systems:
AJ-V6 ENGINE
Single control module
A single Powertrain Control Module (PCM) performs
both engine and transmission control functions. This
Student Guide covers only the engine management
portion of the PTEC system.
SCP Network
PTEC communicates only on the vehicle SCP (Standard
Corporate Protocol) multiplex network.
Returnless fuel system
The fuel delivery system is a supply only system with no
provision for returning unused fuel from the fuel rail to the
fuel tank.
Full authority throttle
PTEC employs a full authority electronic throttle assembly with no cable connection between the accelerator
pedal and the throttle. The throttle assembly incorporates a separate control module with diagnostic
capabilities.
Variable intake system (V6)
V6 engines are equipped with a variable length air
intake manifold that optimizes engine torque across the
entire speed/load range.
Fail safe cooling (V6)
PTEC.02
V6 engines have a PCM “fail safe cooling” strategy that
allows for limited engine operation with low or no
coolant.
NOTES
1.4
Student Guide
Service Training
PTEC CONTROL SUMMARY
The engine management systems for the 3.0 liter AJ-V6 engine and the 4.0 liter AJ28 V8 engine vehicles are virtually
identical in function with differences in the control module parameters and the location of some components.
The major differences between the two systems are as follows:
AJ-V6
AJ28 V8
Two position VVT (variable valve timing)
Variable air intake system
EGR (exhaust gas recirculation) – 2000 MY only
Continuously variable VVT (variable valve timing)
AAI (air assisted injection)
The PTEC powertrain control module (PCM) directly governs the following functions:
• Air assisted fuel injection (V8 only)
• Air conditioning compressor
• Automatic transmission
• Cooling system radiator fan
• Cruise control
• Default operating modes
• Engine power limiting
• Engine speed limiting
• Engine torque reduction control
• Evaporative emission control
• Exhaust emission control
• Exhaust gas recirculation (V6 only)
• Fail safe engine cooling
• Fuel delivery and injection (fuel pump via RECM)
• Fuel system leak check
• Full authority electronic throttle (via Throttle Actuator Control Module)
• Idle speed
• Ignition
• OBD II diagnostics
• Variable intake manifold tuning (V6 only)
• Variable intake valve timing
• Vehicle speed limiting
NOTES
Student Guide
1.5
Service Training
System Logic – V6
V6 ENGINE MANAGEMENT
TACM
DPFE
EGR
VALVE
TP SENSOR
IMT VALVES
IAT SENSOR
MAF SENSOR
CMP SENSOR 2
VVT VALVE 2
IP SENSOR
EFT SENSOR
FI
CMP SENSOR 1
FI
ON-PLUG
COIL
ON-PLUG
COIL
CHT SENSOR
VVT VALVE 1
KS 2
HO2 SENSOR 1/1
KS 1
HO2 SENSOR 2/1
EOT
SENSOR
BANK 1
CKP
SENSOR
BANK 2
HO2 SENSOR 1/2
HO2 SENSOR 2/2
880 PTEC.03
1.6
Student Guide
Service Training
V6 PCM ENGINE MANAGEMENT INPUTS AND OUTPUTS
BATTERY POWER
(KEEP ALIVE MEMORY)
FUEL INJECTORS
IGNITION COILS
VVT 1
MAF
VVT 2
IMT (TOP)
IAT
CHT
IMT (BOTTOM)
CKP
EGR
CMP 1
DATA
CMP 2
FUEL PUMP DIAGNOSTICS (SCP)
KS 1
KS 2
RECM
FUEL PUMP
HO2S 1/1
HO2S 1/2
COOLING FAN
HO2S 2/1
A/C COMPRESSOR RELAY
HO2S 2/2
IP
MAIN
PROCESSOR
DATA
EFT
APP 1, 2, 3
THROTTLE DIAGNOSTICS (SCP)
TACM
THROTTLE MOTOR
TP 1, 2, 3
TP SENSORS
EOT
DPFE
EVAP CANISTER PURGE VALVE
BRAKE ON / OFF
EVAP CANISTER CLOSE VALVE
PSP
FTP
THROTTLE
MONITOR
PROCESSOR
DATA
SCP
DATA
SERIAL COMMUNICATIONS
DATA
FLASH PROGRAMMING
CRUISE CONTROL
BRAKE CANCEL
A/C PRESSURE SENSOR
GENERATOR LOAD
AIRBAG DEPLOY
POWERTRAIN CONTROL MODULE
880 PTEC.04
Student Guide
1.7
Service Training
System Logic – V8
V8 ENGINE MANAGEMENT
MAF SENSOR
TP SENSOR
IAT SENSOR
AAI
VALVE
EFT SENSOR
TACM
IP SENSOR
CMP SENSOR 1
ON-PLUG
COIL
FI
FI
CMP SENSOR 2
ON-PLUG
COIL
ECT
SENSOR
VVT
VALVE
VVT
VALVE 2
KS
HO2 SENSOR 1/1
HO2 SENSOR 2/1
BANK 1
BANK 2
CKP
SENSOR HO2 SENSOR 2/2
HO2 SENSOR 1/2
EOT SENSOR
880 PTEC.05
1.8
Student Guide
Service Training
V8 PCM ENGINE MANAGEMENT INPUTS AND OUTPUTS
BATTERY POWER
(KEEP ALIVE MEMORY)
FUEL INJECTORS
IGNITION COILS
VVT 1
MAF
VVT 2
AAI
IAT
ECT
CKP
CMP 1
DATA
FUEL PUMP DIAGNOSTICS (SCP)
CMP 2
KS 1
RECM
FUEL PUMP
KS 2
HO2S 1/1
HO2S 1/2
COOLING FAN
HO2S 2/1
A/C COMPRESSOR RELAY
HO2S 2/2
EFT
MAIN
PROCESSOR
DATA
IP
THROTTLE DIAGNOSTICS (SCP)
TACM
APP 1, 2, 3
TP 1, 2, 3
THROTTLE MOTOR
TP SENSORS
EOT
BRAKE ON / OFF
PSP
FTP
CRUISE CONTROL
BRAKE CANCEL
THROTTLE
MONITOR
PROCESSOR
DATA
SCP
DATA
SERIAL COMMUNICATIONS
DATA
FLASH PROGRAMMING
A/C PRESSURE SENSOR
GENERATOR LOAD
AIRBAG DEPLOY
COOLANT LEVEL
(NOT PART OF ENGINE MANAGEMENT)
880 PTEC.06
Student Guide
1.9
1.10
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
POWERTRAIN CONTROL
MODULE (PCM)
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
•
•
•
The PCMs for all S-TYPE Jaguars are almost identical
but with unique programming for the characteristics
of the various powertrain combinations. Also, some
minor differences are required in the interface circuits to accommodate the sensors and actuators used
on AJ-V6 or AJ28 engines.
The vehicle powertrain configuration information
and the vehicle identification number (VIN) are flash
programmed into the PCM during vehicle production.
Volatile memory Quiescent current from the vehicle battery is used to maintain OBD generated DTCs
and adaptive values are maintained. If the vehicle
battery is disconnected, stored DTCs and adaptive
values will be lost. The ECM will “relearn” adaptive
values during the next driving cycle.
880 PTEC.07
NOTE: If the PCM or Instrument Pack are replaced, PDU must be used to match the control modules
before the vehicle is operated.
CAUTION: The PCM must not be switched from one vehicle to another; the VIN will be mismatched and the powertrain configuration information may be incorrect for the vehicle.
PCM Power Supplies
•
•
•
•
•
•
•
•
The PCM power supplies flow through a 40 Amp fuse to powertrain control relay 1.
Powertrain control relay 2 supplies power to the A/C compressor clutch, generator, HO2S heaters, and coilon-plug ignition coils.
Both relays are located in the front power distribution board and are powered by the same fuse. 5 Amp fused
B+ voltage activates the relays directly from the ignition switch when it is in positions II (RUN) and III (START).
The PCM is located on the passenger side of the cabin below the climate control blower unit.
The 150-way three-pocket connector housing protrudes through the bulkhead to accept the matching connectors from the engine bay side harnesses.
The 60-way socket connects to the engine harness (PI).
The 32-way socket connects to the transmission harness (GB).
The 58-way socket connects to the vehicle forward harness (FH).
PCM Configuration
NOTE: Once a PCM is configured to a vehicle, it cannot be re configured to another vehicle.
After a PCM is replaced and the battery reconnected, connect WDS. Select Guided Diagnostics from the Main Menu
followed by Vehicle Set Up and Vehicle CM Set Up / Configuration. WDS will perform the configuration during
which you will be prompted to enter the Vehicle Identification Number.
During configuration WDS writes vehicle identification information into a section of the PCM memory called the VID
Block (Vehicle Identification Block). Once the VID Block space is occupied, it cannot be overwritten. The VID Block
stores data pertaining to certain other vehicle control modules. For example, the instrument pack identification data.
2.2
Student Guide
Service Training
The VID Block has no effect on vehicle operation and is accessible in the future via WDS. The intent of the VID Block
is to give Jaguar technicians information on the programmed status of control modules, in the event of a problem.
NOTE: The PCM must be configured to the instrument pack as part of the security system set up. If this is
not carried out, the engine will not start.
POWERTRAIN CONTROL MODULE LOCATION (LHD SHOWN)
880 PTEC.08
POWERTRAIN CONTROL MODULE FACE
FH
GB
PI
1
13
23
12
22
29
1
8
14
7
13
16
1
13
23
30
37
47
36
46
58
17
20
26
19
25
32
31
39
49
12
22
30
38
48
60
880 PTEC.09
Student Guide
2.3
Service Training
Barometric Pressure
The PCM does not incorporate a barometric pressure sensor. Instead, it calculates barometric pressure based on
input signals received from the mass air flow sensor and the throttle position sensor. If the PCM cannot calculate
barometric pressure (failure mode), it defaults to an atmospheric pressure of 27 in. Hg. (902 mBar).
PCM Multiplex and Serial Data Communications
The PCM is part of the SCP vehicle multiplex data network that operates at 41.6 kb per second. In addition to the
SCP network, the PCM is connected to the Serial Data Link, and has a dedicated flash programming circuit. All three
circuits are accessed at the Data Link Connector (DLC) for DTC retrieval, system diagnostics and monitoring, and
PCM EPROM flash programming.
Idle Speed Adaptions
If the vehicle battery is disconnected, idle speed adaptions will be lost. After battery reconnection, operate the vehicle as follows to restore the idle speed adaptions:
• Start the engine and warm to >82 °C (180 °F)
• Switch off the engine; restart the engine
• Idle in Neutral for two (2) minutes
• Depress and hold brake pedal; select Drive; idle for two (2) minutes
System Diagnostics – Faults / Default Action
The PCM continuously performs diagnostic monitoring for OBD II and non-OBD II functions. Diagnostics include:
self-test routines, engine and transmission function monitoring, individual sensor circuit, signal, function and integrity monitoring, and critical sensors input signal validation. Detected faults are logged in the PCM memory as DTCs.
In most instances of detected sensor and/or component failure, the PCM takes default action. Specific default
actions, messages and warnings are contained in the Jaguar Quick Reference Diagnostic Guide: S-TYPE POWERTRAIN DTC Summaries.
NOTES
2.4
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1 PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
PCM SENSING COMPONENTS –
ENGINE
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
Mass Air Flow (MAF) Sensor
MAF SENSOR
•
•
•
•
880 PTEC.10
•
MAF AND IAT SENSOR LOCATION
The MAF sensor measures the mass of air entering
the intake system, the measurement being based
on the constant temperature hot wire principle.
A hot wire probe and an air temperature probe are
Suspended in the air intake tract.
The PCM ensures that the hot wire probe is always
200 °C hotter that the air temperature probe.
The hot wire probe is cooled by the air flowing
through the intake system and the PCM varies the
heating current to maintain the 200 °C temperature difference.
The change in heating current is measured as a
voltage drop across a precision resistor and is
assigned to a corresponding mass air flow calculation by the PCM.
IAT SENSOR
MAF SENSOR
Intake Air Temperature (IAT) Sensor
•
•
•
•
The IAT sensor, located in the air induction duct, is
a thermistor which has a negative temperature
coefficient (NTC).
Intake air temperature is determined by the PCM
by the change in the sensor resistance.
The PCM applies stable 5 volts to the sensor and
monitors the voltage across the pins to detect the
varying resistance.
The PCM uses the IAT signal to adjust ignition timing to match intake air temperature.
NOTES
880 PTEC.11
IAT SENSOR
880 PTEC.12
3.2
Student Guide
Crankshaft Position (CKP) Sensor
•
•
•
•
•
Service Training
CKP SENSOR – V6
The CKP sensor is an inductive pulse generator,
which provides the PCM with an engine speed and
position alternating voltage signal.
The PCM uses the CKP signal to determine both
engine speed and crankshaft position.
The 36-tooth (minus one tooth) reluctor is located on
the crankshaft at different locations in the V6 and V8.
– V6 sensor is located on the front of the crankshaft,
in the front timing cover.
– V8 sensor is located on the transmission drive
plate as in previous V8 engines.
The missing tooth gap provides a PCM reference for
crankshaft position.
– V6 gap is located at 60° BTDC cylinder 1/1.
– V8 gap is located at 50° BTDC cylinder 1/1.
The PCM requires the input signal from the camshaft position sensor to determine the engine
stroke.
880 PTEC.13
CKP SENSOR RELUCTOR – V6
NOTES
880 PTEC.14
CKP SENSOR RELUCTOR – V8
880 PTEC.15
Student Guide
3.3
Service Training
Camshaft Position (CMP) Sensors
CMP SENSOR AND RELUCTOR – V6
RELUCTOR
•
•
•
880 PTEC.16
CMP SENSOR RELUCTOR – V8
•
•
The CMP sensors are inductive pulse generators
which provide the PCM with a cylinder identification alternating voltage signal.
The PCM uses the CMP signals (one for each cylinder bank) for:
– cylinder identification to control starting, fuel
injection sequential operation
– ignition timing
– variable valve timing operation and diagnostics.
The CMP reluctors are located on the inlet camshafts at the rear of the cylinder heads.
– V6 reluctors have four teeth (three are equally
spaced)
– V8 reluctors have five teeth (four are equally
spaced).
The multi-tooth cam sensor rings increase the cam
position feedback frequency, providing the
enhanced control required by the VVT system.
The use of multi-tooth sensor rings also improves
starting by providing additional reference points
for the PCM to determine camshaft position.
880 PTEC.17
NOTES
3.4
Student Guide
Service Training
Engine Coolant Temperature (ECT) Sensor (V8)
•
•
•
The V8 ECT sensor, located on the coolant outlet
elbow between the cylinder banks, is a thermistor
which has a negative temperature coefficient (NTC).
Engine coolant temperature is determined by the
PCM by the change in the sensor resistance.
The PCM applies 5 volts to the sensor and monitors the voltage across the pins to detect the varying resistance.
ECT SENSOR (V8)
880 PTEC.18
PTEC Temperature Sensors
The following Temperature / Resistance / Voltage chart applies to all of the PTEC Temperature Sensors except for the
Cylinder Head Temperature (CHT) Sensor:
•
•
•
•
•
Engine Coolant Temperature (ECT) Sensor
Engine Fuel Temperature (EFT) Sensor
Engine Oil Temperature (EOT) Sensor
Intake Air Temperature (IAT) Sensor
Transmission Fluid Temperature (TFT) Sensor
NOTES
Temperature
°C
°F
Nominal
Resistance
Nominal
Voltage at PCM
0
32
95.851 kΩ
3.88 v
10
50
59.016 kΩ
3.52 v
20
68
37.352 kΩ
3.09 v
30
86
24.239 kΩ
2.62 v
40
104
16.092 kΩ
2.15 v
50
122
10.908 kΩ
1.72 v
60
140
7.556 kΩ
1.34 v
70
158
5.337 kΩ
1.04 v
80
176
3.837 kΩ
0.79 v
90
194
2.840 kΩ
0.61 v
100
212
2.080 kΩ
0.47 v
110
230
1.564 kΩ
0.36 v
120
248
1.191 kΩ
0.28 v
130
266
0.918 kΩ
0.22 v
140
284
0.715 kΩ
0.17 v
150
302
0.563 kΩ
0.14 v
Student Guide
3.5
Service Training
Cylinder Head Temperature (CHT) Sensor (V6)
•
The CHT sensor, located between the two rear coil-on-plug units in the bank 2 cylinder head, is a thermistor
which has a negative temperature coefficient (NTC).
The sensor directly monitors the metal temperature of the cylinder head. This method of engine heat sensing
is used in place of an engine coolant temperature sensor to enable the V6 fail safe cooling strategy to operate.
Refer to page 10.4. The use of a metal temperature sensor allows cylinder head temperature to be measured
even if coolant has been lost.
Cylinder head temperature is determined by the PCM by the change in the sensor resistance. The PCM applies
5 volts to the sensor and monitors the voltage across the pins to detect the varying resistance.
•
•
V6 Cylinder Head Temperature Sensor
CHT SENSOR (V6)
Temperature
°C
°F
880 PTEC.19
CHT SENSOR LOCATION (V6)
0
10
20
32
50
68
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
86
104
122
140
158
176
194
212
230
248
266
284
302
320
338
Nominal
Resistance
Nominal
Voltage at PCM
96.248 kΩ
59.173 kΩ
37.387 kΩ
4.140 v
3.737 v
3.257 v
24.216
16.043
10.851
7.487
5.269
3.775
2.750
2.038
1.523
1.155
0.887
0.689
0.542
0.430
0.345
2.738 v
2.226 v
1.759 v
1.362 v
1.043 v
0.794 v
0.604 v
0.462 v
0.354 v
0.273 v
0.212 v
0.167 v
0.132 v
0.105 v
0.085 v
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
NOTES
880 PTEC.20
3.6
Student Guide
Service Training
Engine Oil Temperature (EOT) Sensor
•
•
•
•
•
The PCM uses the EOT signal for variable valve timing control.
The EOT sensor is a thermistor which has a negative temperature coefficient (NTC).
The PCM applies 5 volts to the sensor and monitors the voltage across the pins to detect the varying resistance.
Engine oil temperature is determined by the PCM by the change in the sensor resistance.
The V6 and V8 sensors are fitted to the engine lubrication system in different locations:
– V6 EOT sensor is located on the left hand side of the cylinder block in the oil return channel from the oil cooler
– V8 EOT sensor is located on the oil cooler / filter adapter.
EOT SENSOR – V6
OIL PRESSURE
SWITCH
EOT SENSOR
880 PTEC.21
NOTES
EOT SENSOR – V8
EOT SENSOR
OIL PRESSURE SWITCH
880 PTEC.22
Student Guide
3.7
Service Training
Power Steering Pressure (PSP) Switch
PSP SWITCH – V6 SHOWN
•
•
•
The PCM uses the input from the PSP switch to
compensate for the additional accessory drive load
on the engine by adjusting the engine idle speed
and preventing engine stall during parking maneuvers.
The PSP switch, located on the PAS pump outlet
pipe, monitors the hydraulic pressure on the high
pressure side of the power steering system.
The switch is a normally open switch that closes
when the hydraulic pressure reaches 24.13 ± 3.45
Bar (350 ± 50 psi).
880 PTEC.23
Brake Switches
The PCM receives input signals from two brake pedal position switches:
• Brake switch (B+ voltage / normally open)
• Brake cancel switch
Two switches provide signal plausibility.
• The switch inputs to the PCM are used for cruise control cancel and multiple vehicle functions (via SCP).
– On DSC equipped vehicles, the brake switch is hard wired to the DSC control module.
The DSC system uses an active brake booster, which when activated by the DSCCM, will cause the brake pedal to
drop with the subsequent activation of the brake switches. During the DSC self test when the vehicle first moves off,
the booster is momentarily activated by the DSCCM causing the brake pedal to drop.
When the DSCCM is performing the self test, it does not broadcast an SCP BRAKES APPLIED message, which prevents erroneous brake light activation.
NOTES
3.8
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
INDUCTION AIR AND THROTTLE CONTROL
Air Induction Systems
The V6 and V8 engines have air induction systems that are similar from the air cleaner inlet through the throttle
body. The systems consist of the normal components with the MAF sensor located in the air cleaner outlet and the
IAT sensor located in the air intake duct just downstream of the MAF sensor. Resonator chambers are fitted to the
intake ducting to control intake air reverberation at certain throttle openings.
After exiting the throttle body, the V6 and V8 induction air systems differ greatly.
AIR INDUCTION: V8
THROTTLE BODY
MAF SENSOR
INTAKE DUCTING
THROTTLE BODY ADAPTOR
AIR CLEANER
IAT SENSOR
880 PTEC.25
AIR INDUCTION: V6
TUNED MANIFOLD ASSEMBLY
THROTTLE BODY
IAT SENSOR
MAF SENSOR
4.2
Student Guide
INTAKE DUCTING
AIR CLEANER
880 PTEC.24
Service Training
Air Intake – V8
Induction air flows into the manifold through a centrally located inlet. The manifold incorporates the air rails for air
assisted fuel injection. The heated (engine coolant) throttle adapter connects the throttle body to the manifold and
provides EVAP, and vacuum source connections. The air assist injection valve is located on the throttle adapter. A
noise isolation pad locates between the induction manifold and the engine vee.
INTAKE MANIFOLD, THROTTLE ADAPTOR AND ISOLATION PAD – V8
VACUUM CONNECTIONS
AAI AIR RAIL
EVAPORATIVE EMISSIONS INLET
AAI VALVE INLET
AAI VALVE OUTLET
NOISE ISOLATION PAD
AAI VALVE
PART LOAD BREATHER INLET
COOLANT PIPES
880 PTEC.26
Student Guide
4.3
Service Training
Full Authority Throttle Control
The electronic throttle control system used in the PTEC engine management systems is designed with no mechanical connection between the vehicle accelerator pedal and the throttle valve. The PCM has full authority over
throttle valve movement.
Accelerator pedal position is monitored by APP (accelerator pedal position) sensors that are hard wired to the PCM.
The PCM calculates a throttle plate opening appropriate for the vehicle operating conditions using:
• pedal position
• engine speed
• vehicle speed
• cruise control status
• power reduction requirements for traction control, transmission torque input limits, and torque modulation
required during transmission shifting.
The PCM issues redundant PWM throttle position command signals via hard wired connections to the throttle actuator control module (TACM), which is located on the throttle body assembly. The TACM drives the throttle valve to
the desired position via the throttle drive motor.
Throttle position sensors communicate actual throttle angle feedback to the PCM via hard wires to provide closed
loop control. The TACM communicates calculated throttle position to the PCM via hard wire connection as a crosscheck.
The throttle control system uses multiple accelerator pedal position sensors, throttle position sensors, and multiple
hard wired signals that allow the PCM to monitor individual signal validity. Two separate, dedicated, twisted pair
(B+ around ground) provide supply power and ground to the TACM.
A dedicated electronic throttle monitor microprocessor, within the PCM, constantly monitors overall operation of
the throttle control system. The throttle monitor microprocessor interfaces internally with the PCM main microprocessor logic and software.
In the event of a software or component failure, the system alerts the driver and, depending on the failure, adopts a
default action to ensure driver safety. Refer to the Jaguar Quick Reference Diagnostic Guide: S-TYPE POWERTRAIN
DTC Summaries.
Operation of the system is designed to be totally transparent to the driver with a total delay of less than 70 ms
between pedal actuation and throttle movement.
Throttle Data Recorder
The PCM throttle monitor processor incorporates a throttle data recorder. If the throttle data recorder is stopped by
an airbag deployed input, the current throttle data is retained in memory and the PCM main processor flags DTC
P1582. The throttle data recorder will not function again until 100 ignition key cycles have been completed. The
logged DTC P1582 will require an additional 40 key cycles to clear, or the DTC can be cleared using PDU.
Throttle Motor Control Relay, 2001 Model Year ON
2001 Model Year ON PTEC systems have a PCM internal timer circuit to control a throttle motor control relay. This
circuit allows the PCM to open the throttle, via the relay, after engine OFF to prevent exhaust gas from building-up
in the intake manifold and creating difficult hot start conditions.
4.4
Student Guide
Service Training
THROTTLE CONTROL LOGIC
INTAKE AIR
THROTTLE MOTOR
THROTTLE POSITION
SENSORS
THROTTLE
MONITOR
PROCESSOR
MOTOR
POSITION
ACCELERATOR PEDAL
POSITION SENSORS
MOTOR
DRIVE
THROTTLE ACTUATOR
CONTROL MODULE
MAIN
PROCESSOR
ACTUAL THROTTLE ANGLE
ACCELERATOR
PEDAL
PWM
PWM
DIAGNOSTICS: SCP
B+
B+
POWERTRAIN
CONTROL MODULE
THROTTLE MOTOR CONTROL RELAY – 2001 MY ON
THROTTLE ACTUATOR
CONTROL MODULE
B+
B+
O
POWERTRAIN
CONTROL MODULE
THROTTLE MOTOR
CONTROL RELAY
B+
B+
880 PTEC.27
Student Guide
4.5
Service Training
Throttle Body Assembly
The throttle body assembly consists of the following sub components:
• Throttle body with valve and shaft
• Throttle actuator control module (TACM)
• Drive motor unit
• Throttle position (TP) sensor assembly
Because each throttle assembly is calibrated during assembly, no adjustments to the assembly or its components are required
or permitted. The throttle body must not be disassembled. The only serviceable component is the TP sensor assembly.
Throttle body
THROTTLE BODY ASSEMBLY
TP SENSOR
THROTTLE BODY
THROTTLE DRIVE
MOTOR UNIT
The throttle body is an aluminum casting with a 70 mm
(2.75 in.) intake bore. The throttle valve and shaft
rotate on ball bearings with an internal tooth quadrant
gear and two throttle return springs on the drive end of
the shaft. Factory adjusted and sealed stop screws set
the throttle closed and full open positions.
Throttle drive motor unit
The throttle drive motor unit consists of the motor and
an integral position encoder. If the motor fails, the
throttle return springs return the throttle valve to the
closed position.
WARNING: DO NOT PUT YOUR FINGERS
IN THE THROTTLE BODY BORE. THEY
COULD BE INJURED IF TRAPPED BY THE
THROTTLE PLATE.
THROTTLE ACTUATOR
CONTROL MODULE
880 PTEC.28
CAUTION: Do not attempt to clean the
throttle housing or remove any sealant
from the assembly. Any air leakage will
disturb the idle speed calibration.
NOTES
4.6
Student Guide
Service Training
Accelerator Pedal Position (APP) Sensor Assembly
•
•
•
Three individual rotary potentiometers comprise the
APP sensor assembly located at the top of the accelerator pedal.
The potentiometers are driven by the accelerator
pedal pivot shaft and provide separate analog voltage
signals to the PCM proportional to accelerator pedal
movement and position.
The accelerator pedal uses two return springs to
provide a positive return if one should fail, and to
simulate the feel of a conventional accelerator
pedal.
APP SENSOR
Each potentiometer has separate reference voltage and
reference ground circuits hard-wired to the PCM; each
provides its unique pedal position signal (via hard-wire
connection) directly to the PCM. The PCM detects
faults by comparing each pedal position signal to
expected values as shown in the chart below.
PCM throttle control
The command signal duty cycle is increased as more
throttle opening is required. Duplicate throttle command signals are transmitted to the throttle actuator
control module (TACM) over separate wires.
NOTES
880 PTEC.29
APP SENSOR CHARACTERISTIC
5
APP 2
4
NOMINAL VOLTAGE OUTPUT
The PCM calculates a required throttle position from
the APP input signals and applies engine speed, cruise
control status, engine torque reduction requirements,
and other applicable data to generate duplicate 256 Hz
PWM throttle command signals.
APP 3
3
2
1
APP 1
NOMINAL ROTATION
0
-3˚
0˚
5˚
10˚
15˚
DEGREE OF PEDAL ROTATION
880 PTEC.30
Student Guide
4.7
Service Training
Throttle Actuator Control Module (TACM)
The TACM has two connectors and mounts to the throttle body and motor assembly. One connector plugs directly
into the throttle motor. The second connector is the main interface with the PCM and also carries the twisted pair
B+ voltage and ground supplies for TACM and throttle motor drive power. The two separate B+ voltage supplies
from the front power distribution boxes are switched by powertrain relay 1 and the two separate ground supplies
share the main ground stud used by the PCM.
The TACM processes the two throttle command PWM signals from the PCM and drives the throttle motor to the
required position. The motor’s position feedback to the TACM provides closed loop control and enables the TACM
to maintain the desired throttle valve position. The PCM monitors actual throttle valve angle via the three-element
TP sensor signals.
The TACM is on the SCP multiplex network and communicates with the PCM only for diagnostic purposes.
In addition to motor drive and positioning, the TACM also performs the following functions:
• Self diagnostics
• PCM throttle command signals validity comparison
• Requested throttle angle to actual throttle angle comparison
• Drive motor circuit operational comparison
• Failed throttle return spring detection
• Drive motor internal circuit continuity monitoring
• Inductive position encoder failure and out of range signals monitoring
• SCP transmission of diagnostic data to the PCM
NOTES
4.8
Student Guide
Service Training
Throttle Position Sensor (TPS) Assembly
The throttle position sensor assembly consists of three
Hall effect sensing elements with conditioning circuits
that are directly driven by the throttle valve shaft.
TP SENSOR
Each sensing element has separate reference voltage
and reference ground circuits hard-wired to the PCM;
each provides its unique throttle position signal (via
hard-wire connection) directly to the PCM. The unique
characteristics of each signal are used for identification,
similar to the APP Sensor signals.
NOTES
880 PTEC.31
TP SENSORS GENERAL CHARACTERISTICS
TP 2
OUTPUT VOLTAGE
TP 3
TP 1
V
DEGREES
SENSOR ROTOR ANGLE
880 PTEC.32
Student Guide
4.9
Service Training
Cruise Control
The cruise control system is fully integrated within PTEC. The PCM maintains the driver selected vehicle speed to
within ±1 mph (1.5 km/h) via the normal throttle control and other engine and transmission control functions. The
system uses inputs from illuminated steering wheel mounted ON / OFF, SET / ACCEL, COAST, CANCEL, and
RESUME switches, the two brake pedal switches (normally open Brake Switch, normally closed Brake Cancel
Switch), and vehicle speed. Cruise control is operational between 25 – 130 mph (40 – 209 km/h).
The cruise control strategy within the PCM uses engine control to provide smooth acceleration and deceleration.
In cases such as driving downhill, where the vehicle tends to exceed the cruise control set speed, the PCM uses an
engine braking strategy and transmission downshifts to help maintain the desired speed.
Cruise control switch functions
ON / OFF
When the system is switched ON or OFF, the PCM broadcasts an SCP VEHICLE SPEED CONTROL ON/OFF message. A SPEED CONTROL ON or OFF message is displayed in the message center for 4 seconds accompanied by a
single audible chime. The PCM also broadcasts an SCP VEHICLE SPEED CONTROL SET SPEED ENABLE/DISABLE
message whenever the Speed Control Set lamp in the instrument pack should be switched ON or OFF.
SET / ACCEL
Touching the SET / ACCEL switch with the cruise control switched ON and vehicle speed in the operating range puts
the system into SET mode. The current vehicle speed is memorized and maintained. If the switch is held in the
active position the vehicle will accelerate smoothly until it the switch is released. If the switch is touched momentarily (less than 640 ms), the vehicle speed increases by 1 mph. Pressing the accelerator pedal will accelerate the
vehicle higher than the memorized speed without disengaging cruise control. When the pedal is released, the vehicle smoothly decelerates to the memorized speed.
COAST
Touching the COAST switch momentarily (less than 640 ms) decelerates the vehicle 1 mph. Holding the switch
allows the vehicle to decelerate until the switch is released. When the switch is released, the vehicle will maintain
the current speed.
CANCEL
Touching the CANCEL switch or applying the brakes puts the system into STANDBY mode and allows the vehicle to
decelerate until either the SET / ACCEL or the RESUME switch is activated.
RESUME
When the system is STANDBY mode, touching the RESUME switch accelerates the vehicle to the memorized set
speed. Resume will not function if the system has been switched OFF, the ignition has been switched OFF, or the
vehicle is below the minimum operational speed.
NOTES
4.10
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
5.2
Student Guide
Service Training
Service Training
Electronic Returnless Fuel System
The electronic returnless fuel system used with the PTEC engine management system provides pressurized fuel at
the fuel injectors and does not require a return line with its associated hardware. Additional benefits of the system
include:
• Precise fuel pressure control
• Reduced fuel temperature and fuel tank vapor caused by constant fuel recirculation
• Reduced electrical system load
• Fuel pressure boost to prevent fuel vapor lock
• Reduce hot start cranking time
Fuel delivery volume and pressure from the single in-tank fuel pump are controlled by the PCM in a closed loop.
The actual fuel pump “drive” is supplied and controlled by the Rear Electronic Control Module (RECM), which
receives fuel pump control input from the PCM. The PCM / RECM fuel pump control circuit is hard wired.
The system delivers the correct amount of fuel to the engine under all conditions and at a constant pressure differential
with respect to manifold absolute pressure, without the need for a return line to the tank or a fuel rail pressure regulator.
ELECTRONIC RETURNLESS FUEL SYSTEM
FUEL FILTER
ENGINE FUEL
TEMPERATURE SENSOR
FUEL INJECTORS
INJECTION
PRESSURE
SENSOR
FUEL INJECTORS
FUEL RAIL
FUEL TANK
TPTEC.77
NOTES
Student Guide
5.3
Service Training
Electronic Returnless Fuel System (continued)
Fuel tank (Jaguar S-TYPE)
JAGUAR S-TYPE FUEL TANK AND
EVAP CANISTERS (UNDERFLOOR)
EVAP CANISTER ASSEMBLY
FUEL FILLER
(PIPE REMOVED)
The plastic blow-molded fuel tank is a saddle shape
tank with LH and RH fuel compartments. The tank is
located below the rear passenger seat with the drive
shaft and exhaust running through the arch of the tank.
The underside of the tank is protected by a heat shield.
The tank assembly is retained by two metal straps
which are fixed to the underbody at the front by removable hinge pins and at the rear by bolts.
Refueling is via a separate filler pipe and connecting
hose to a stub pipe on the RH fuel compartment.
A variable speed fuel pump is located in the RH compartment. Jet pumps are located in both compartments
with external crossover pipes for fuel transfer between
the compartments. The crossover pipes and electrical
connectors exit the fuel tank through top plates which
are secured in the tank using screw-on closure rings.
The components on the top of the fuel tank are accessible from inside the vehicle via two access holes in the
floor panel, below the rear seat.
FUEL TANK ASSEMBLY
880 PTEC.33
Fuel filter
The replaceable in-line fuel filter is located in the back
of the left wheel well. All fuel supply lines use quick-fit
connections that require a Jaguar service tool.
NOTES
5.4
Student Guide
Service Training
JAGUAR S-TYPE FUEL TANK ASSEMBLY
FLOAT LEVEL
VENT VALVE
FUEL PUMP
CONNECTORS
GRADE VENT
VALVE
PRESSURE RELIEF
VALVE
TO EVAP
CANISTER
HEAT SHIELD
TANK RETAINING
STRAP
FUEL TRANSFER
PIPES
FUEL TO ENGINE
VAPOR TO EVAP VALVE
FRONT OF VEHICLE
880 PTEC.34
Student Guide
5.5
Service Training
Fuel flow
•
•
The variable speed fuel pump is contained in a fuel reservoir in the RH compartment.
Fuel is pumped from the reservoir through an external crossover pipe to the LH compartment where it flows
via a ‘T’ junction to the parallel pressure relief valve and then out to the engine fuel rail.
• The reservoir fuel level is maintained by the continual flow of fuel supplied by jet pumps in the LH and RH
compartments.
Fuel from the LH compartment is pumped through an external crossover pipe to the reservoir. The RH compartment jet pump is located in the base of the reservoir.
Parallel pressure relief valve
The parallel pressure relief valve assembly contains two spring-loaded valves, which operate in opposite directions:
• The supply valve opens to allow fuel flow at approximately 0.014 Bar (0.2 psi) during normal operation.
• The fuel rail pressure relief valve opens at approximately 4.14 – 4.48 Bar (60 – 65 psi) to relieve excessive fuel
rail pressure.
The main functions of the parallel pressure relief valve assembly are:
• To ensure fast engine starting by “checking” fuel in the supply lines and rail.
• To limit rail pressure due to temporary vapor increase during hot soak conditions (temperature and
thus pressure drop after approximately 20 minutes.)
• To limit rail pressure caused by sudden load changes such as a full to closed throttle transition.
• To prevent siphoning from the tank in the even of the fuel line being severed with the pump inactive.
NOTES
5.6
Student Guide
Service Training
FUEL FLOW
EFT SENSOR
IP SENSOR
FUEL FILTER
FUEL INJECTORS
LH FUEL LEVEL
SENSOR
ELECTRICAL
CONNECTOR
FUEL RAIL
FUEL INJECTORS
RH FUEL LEVEL SENSOR
AND FUEL PUMP
ELECTRICAL CONNECTOR
MANIFOLD
VACUUM
FUEL LEVEL
SENSORS
LH COMPARTMENT
RH COMPARTMENT
FUEL PUMP
PARALLEL PRESSURE
RELIEF VALVE
FUEL RESERVOIR
JET PUMP
JET PUMP
FUEL RAIL PRESSURE RELIEF VALVE
opens at 60 – 65 psi to allow
fuel flow to the fuel tank
SUPPLY VALVE
opens at 0.2 psi to allow
fuel flow to the fuel rail
PARALLEL PRESSURE
RELIEF VALVE
880 PTEC.35
NOTES
Student Guide
5.7
Service Training
Fuel System Sensors
The fuel pump delivers fuel through a single fuel supply line to the closed-ended fuel rail. Two sensors feedback rail
fuel pressure and temperature to the PCM. The IP (injector pressure) sensor is located at the end of the fuel rail, the
EFT (engine fuel temperature) sensor is located at the supply end of the fuel rail.
Fuel injection pressure (IP) sensor
IP SENSOR OUTPUT VOLTAGE vs.
APPLIED DIFFERENTIAL PRESSURE
•
5
•
NOMINAL OUTPUT VOLTAGE
4
•
3
•
2
The IP sensor, located on the fuel rail, is a pressure
transducer device with a diaphragm separating the
pressure transducer from direct contact with the fuel.
A pipe connects the sensor to the intake manifold
for sensing manifold depression (manifold vacuum).
The voltage signal from the transducer is “conditioned” within the sensor.
The PCM receives the conditioned voltage signal,
which is proportional to differential fuel pressure
in the rail.
1
0V
Bar
-0.69
0
0.69
1.38
2.07 2.76
psi
-10
0
10
20
30
40
3.45
4.14
4.83
5.52
50
60
70
80
APPLIED DIFFERENTIAL PRESSURE
880 PTEC.36
NOTES
5.8
Student Guide
Engine fuel temperature (EFT) sensor
•
•
•
•
Service Training
FUEL RAIL – V6
The EFT sensor, located on the fuel rail, is a thermistor which has a negative temperature coefficient
(NTC).
Fuel temperature is determined by the PCM by the
change in the sensor resistance.
The PCM applies a 5 volts to the sensor and monitors
the voltage across the pins to detect the varying resistance.
The PCM uses the EFT signal to adjust fuel pump
pressure to prevent fuel vaporization and ensure
adequate fuel supply to the injectors.
IP SENSOR
FUEL INLET
EFT SENSOR
NOTES
880 PTEC.37
FUEL RAIL – V8
IP SENSOR
FUEL INLET
EFT SENSOR
880 PTEC.38
Student Guide
5.9
Service Training
Fuel pump control and operation
The fuel pump relay, located in the rear power distribution box, supplies power to the RECM to operate the fuel
pump. The relay is activated by ignition switched B+ voltage via the inertia switch.
The PCM calculates engine fuel requirements using:
• engine load
• speed
• air flow
• engine temperatures:
– cylinder head (V6)
– engine coolant (V8)
– intake air
• current fuel rail environment from the IP and EFT sensors.
The PCM communicates the fuel flow demand to the RECM as a pulse width modulated (PWM) signal over a single
line at a frequency of approximately 256 Hz and a duty cycle of 0-50%.
The RECM amplifies this signal by increasing the frequency by 64 and doubling the duty cycle, thus providing the
variable high current drive for the fuel pump.
When the ignition switch is turned from OFF to RUN or START, the PCM primes the system by running the pump for
1 second. After prime, the pump is switched ON when the CKP signal is received. The pump is switched OFF 1 second after the engine is stopped. During all hot fuel conditions, fuel pressure is increased to prevent vapor lock.
Fuel pump drive status is monitored by the RECM and communicated to the PCM via the SCP network.
In the event of a vehicle impact, the inertia switch switches open deactivating the fuel pump relay and causing the
RECM to cancel fuel pump drive.
NOTES
5.10
Student Guide
Service Training
FUEL PUMP CONTROL
IGNITION
SWITCHED POWER
MAF
IAT
CHT / ECT
CKP
PWM
FUEL FLOW DEMAND
IP
EFT
DATA
FUEL PUMP
DIAGNOSTICS (SCP)
PWM
POWERTRAIN
CONTROL MODULE
FUEL PUMP
DRIVE
FUEL PUMP
BATTERY POWER
B+ IGNITION SWITCHED
POWER
FUEL PUMP
DRIVE POWER
INERTIA SWITCH
REAR ELECTRONIC
CONTROL MODULE
FUEL PUMP
RELAY
880 PTEC.39
Fuel level sensors
Outputs from the fuel level sensors are connected by
independent wires to the RECM, which communicates
the LH and RH sensor data independently to the instrument pack and the PCM via the SCP network.
INERTIA SWITCH
Inertia switch
The inertia switch is located behind the trim on the left
side of the vehicle, forward of the front door post and
below the fascia. A finger access hole in the trim allows
the switch to be reset.
If the inertia switch is tripped, it interrupts the ignition
switched B+ voltage supply circuit to the fuel pump relay
coil. The direct B+ voltage fuel pump supply to the RECM
is interrupted and the pump immediately stops.
NOTES
880 PTEC.40
Student Guide
5.11
Service Training
Evaporative Emission Control System
EVAP fuel tank components
To meet ORVR evaporative emission requirements, the tank and associated components are designed to minimize
vapor losses. During refueling, the narrowed fuel filler tube below the nozzle region provides a liquid seal against the
escape of vapor and a check valve in the tank inlet pipe opens to incoming fuel only to prevent splashback. As the
tank fills, vapor escapes through the fuel level float valve, at the top of the tank, and passes through the adsorption
canisters to atmosphere. When the rising fuel level closes the float valve, the resulting back pressure causes refuelling cutoff. While the float valve is closed, any further rise in vapor pressure is relieved by the grade vent valve which
connects to the canisters via the outlet of the float valve. At less than full tank level, the float valve is always open,
providing an unrestricted vapor outlet to the canisters.
If the tank is over filled (e.g. a fault in the delivery system) an integral pressure relief valve in the float valve assembly
opens to provide a direct vent to atmosphere.
The float level vent valve/pressure relief valve assembly and the grade valve are welded to the tank top and are nonserviceable. Note that both valve assemblies incorporate roll-over protection.
The fuel filler cap uses a 1/8 turn action and is tethered to the body. The filler cap assembly incorporates both pressure relief and vacuum relief valves (the latter is a new feature to Jaguar).
EVAPORATIVE EMISSION CONTROL SYSTEM
INTAKE
MANIFOLD
VENT
FILTER
PURGE FLOW
EVAPORATIVE
CANISTER
CLOSE VALVE
EVAPORATIVE
CANISTER
PURGE VALVE
SINGLE
EVAPORATIVE
CANISTER
PURGE FLOW
MANIFOLD VACUUM
DUAL
EVAPORATIVE
CANISTER
PWM
FUEL TANK PRESSURE
FUEL TANK
PRESSURE
SENSOR
GRADE VENT
VALVE
PURGE
CONTROL
STRATEGY
OBD II
LEAK
CHECK
POWERTRAIN
CONTROL MODULE
FUEL TANK
5.12
TPTEC.78
Student Guide
Service Training
EVAP canister assembly
Three series connected EVAP carbon canisters (one single, one dual) are used for vapor storage and are mounted on
a plastic bracket fixed to the underbody above the rear axle.
The EVAP canister close valve and fuel tank pressure sensor are components used by the PCM for leak check monitoring. The EVAP canister close valve is mounted on the canister bracket. The fuel tank pressure sensor is fitted to
the vapor pipe.
JAGUAR S-TYPE EVAP FUEL TANK COMPONENTS
FUEL PUMP
CONNECTORS
FUEL TRANSFER PIPES
JET PUMP ASSEMBLY
CONNECTORS
TO EVAP CANISTER
FTP SENSOR
FUEL TO ENGINE
TO EVAP CANISTER PURGE VALVE
880 PTEC.41
JAGUAR S-TYPE EVAP CANISTER ASSEMBLY
SINGLE
EVAP CANISTER
DUAL
EVAP CANISTER
CONNECTOR
MOUNTING BRACKET
880 PTEC.42
Student Guide
5.13
Service Training
Evaporative Emission Control System (continued)
EVAP canister close valve
SOLENOID
CONNECTOR
MANIFOLD CONTROL
VACUUM
The EVAP canister close valve is a solenoid valve that
closes the canister vent outlet when driven by the PCM.
By closing the vent, the system can be monitored for
leaks.
Fuel tank pressure (FTP) sensor
The FTP sensor is a pressure transducer device. The
voltage signal from the transducer is “conditioned”
within the sensor. The PCM receives the conditioned
voltage signal, which is proportional to the vapor pressure in the fuel tank.
EVAP canister purge valve
880 PTEC.43
The EVAP canister purge valve is mounted on the rear left
hand side of the engine bay. The valve is controlled by the
PCM with a PWM signal driving a solenoid valve, which in
turn applies manifold vacuum to actuate the valve.
NOTES
5.14
Student Guide
Service Training
Crankcase Ventilation System: V6
The closed and part throttle crankcase ventilation system consists of an oil separator, externally mounted to
the cylinder block between the cylinder banks, a springloaded in-line positive crankcase ventilation (PCV) valve,
and a hose to the intake manifold. The intake manifold
hose connection is downstream of the throttle valve and
is warmed by engine coolant to prevent icing.
POSITIVE CRANKCASE VENTILATION: V6
PCV VALVE
OIL SEPARATOR
During closed and part throttle conditions, high manifold vacuum opens the spring loaded PCV valve
allowing crankcase vapors to be drawn through the oil
separator to the intake manifold. Any oil in the vapors
is trapped by the separator and returns to the crankcase. As throttle opening increases, intake manifold
vacuum decreases and the PCV valve closes in proportion to the manifold vacuum decrease.
The full load crankcase ventilation system consists of
breather outlets on each camshaft cover connected to
the intake duct via hoses and a tee connection. At full
and near full load engine operation, intake duct pressure decreases drawing crankcase vapor to the intake
via the hoses and tee connection.
880 PTEC.44
FULL LOAD VENTILATION: V6
NOTES
880 PTEC.45
Student Guide
5.15
Service Training
Crankcase Ventilation System: V8
The V8 full load and part load breather pipes are reconfigured in the Jaguar S-TYPE to accommodate the induction
manifold, camshaft covers and the engine installation.
During idle and part load operation, crankcase vapors are drawn through the bank 1 camshaft cover oil separator to
the heated intake manifold connection downstream of the throttle valve. During full load operation the vapors flow
through the bank 2 camshaft cover oil separator to the intake duct.
Vacuum connections for the EVAP system and the IP Sensor are also shown in the illustration.
JAGUAR S-TYPE CRANCKCASE VENTILATION AND VACUUM CONNECTIONS: V8
AAI VALVE
INLET
EVAP EMISSIONS
PART LOAD
BREATHER
BRAKE SERVO
VACUUM
FULL LOAD
BREATHER
IP SENSOR
VACUUM
VACUUM CONTROL
880 PTEC.46
NOTES
5.16
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
FUEL INJECTION
PTEC fuel injection strategy follows the current standard practice of sequential operation with PCM control
to suit the prevailing engine and vehicle operating
modes and conditions.
FUEL INJECTOR: V8
FUEL SUPPLY
The fuel injectors for the S-TYPE V6 and V8 are of the
twin-spray pintle-type design. The injectors for each
engine have unique flow rates. The V8 injectors are
constructed with a shroud to accommodate the air
assisted injection (AAI) system.
ASSISTED AIR
INLET
TPTEC.47
Fuel injectors are identified by engine bank and cylinder position (bank/position) as follows:
V6
V8
Right hand bank
1/1
1/2
1/3
1/1
1/2
1/3
1/4
Left hand bank
2/1
2/2
2/3
2/1
2/2
2/3
2/4
Fuel injector resistance
V8 (Siemens)
12 Ohms
V6 (Bosch / Ford) 14 Ohms
NOTES
6.2
Student Guide
Service Training
Air Assisted Fuel Injection (V8)
•
•
•
•
•
•
Air assisted injection decreases the formation of
hydrocarbons and improves combustion stability
during cold engine starts by admitting a metered
amount of air to the base of each fuel injector to help
atomize the fuel.
The amount of air admitted reduces progressively
as engine temperature increases.
AAI VALVE (V8)
VALVE SHOWN CLOSED
INLET
OUTLET
The PCM controlled AAI valve is attached to the
throttle body adapter.
The valve controls the air flow volume through the
hoses to the air rails and fuel injectors.
The air rails are part of each bank of the intake manifold.
The difference between intake manifold pressure
and atmospheric pressure causes the air to flow
through the valve.
NOTES
TPTEC.48
AAI VALVE AND AIR DISTRIBUTION
AAI VALVE
TPTEC.49
Student Guide
6.3
Service Training
FUEL INJECTION
Heated Oxygen (HO2) Sensors
•
HO2 SENSOR CHARACTERISTIC
•
800mV
OUTPUT VOLTAGE
•
•
•
200mV
RICHER
λ = 1
(OPTIMUM)
LEANER
TPTEC.50
HO2 SENSOR VOLTAGE SWING TRACE (UPSTREAM)
•
UPSTREAM OXYGEN SENSOR
0.86V
Both the V6 and V8 engines use two conventional
zirconium dioxide heated oxygen sensors for each
cylinder bank.
The oxygen sensors produce a voltage by conducting
oxygen ions at temperatures above 300 °C (572 °F).
The tip portion of the sensor’s ceramic element is
in contact with the exhaust gas.
The remaining portion of the ceramic element is in
contact with ambient air via a filter through the
sensor body.
Sensor output voltage switches between approximately 800 millivolts and 200 millivolts, depending on the oxygen content of the exhaust gas:
– when the air : fuel ratio is richer than optimum,
the oxygen content of the exhaust gas is low
and the voltage output is high
– when the air : fuel ratio is leaner than optimum,
the oxygen in the exhaust is high and the output
voltage is low.
Only a very small change in air : fuel ratio is
required to swing the oxygen sensor voltage from
one extreme to the other, thus enabling precise
fuel metering control.
700mV
NOTES
200mV
0V
10 SWINGS PER MINUTE AT IDLE
TPTEC.51
6.4
Student Guide
Service Training
One sensor is located upstream and one is located downstream of each catalytic converter. The upstream sensors
are used by the ECM for closed loop fuel metering correction. The downstream sensors are used to monitor catalyst
efficiency.
HO2 SENSORS
UPSTREAM
DOWNSTREAM
TPTEC.52
HO2 sensors are identified by engine bank and exhaust position (bank/position) as follows:
Upstream
Downstream
Right hand bank
HO2 sensor 1 / 1
HO2 sensor 1 / 2
Left hand bank
HO2 sensor 2 / 1
HO2 sensor 2 / 2
The HO2 sensor internal electric heaters reduce the time needed to bring the sensors up to operating temperature
and maintain sensor temperature when the exhaust gasses are cool. B+ voltage is supplied to all four heaters from
powertrain relay 2. Each heater has a separate ground circuit to the PCM for control and diagnostics.
Upstream HO2 Sensor heater resistance
3.3 Ω
Downstream HO2 Sensor heater resistance
5.0 Ω
The PCM switches the upstream heaters ON at 100% for about 10 seconds during engine cranking, then controls the
voltage to maintain sensor temperature above 350 °C (662 °F). This action provides fast “light off”. The downstream HO2 sensors operate in the cooler exhaust gas exiting from the catalytic converter and are always ON while
the engine is running.
NOTE: The upstream sensors connect to the engine (PI) harness and the downstream sensors connect to
the transmission (GB) harness.
THE UPSTREAM AND DOWNSTREAM SENSORS ARE NOT
INTERCHANGEABLE.
Student Guide
6.5
Service Training
FUEL INJECTION
Catalytic Converters
CATALYTIC CONVERTER
Each two-element catalytic converter is attached to its
exhaust manifold with a two bolt self sealing flange.
The resonator and muffler assemblies connect to the
converter outlets with Torca clamps. The entire
exhaust system can be serviced from under the vehicle.
TPTEC.53
NOTES
6.6
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
IGNITION
PTEC ignition strategy follows the current standard
practice of PCM control from a base ignition map,
which is then corrected for the specific engine operating conditions. Ignition is synchronized by the PCM
using the input signals from the CKP and CMP sensors.
BASE IGNITION MAP (TYPICAL)
IGNITION ANGLE
ED
SPE
INE
ENG
LOA
D
880 PTEC.54
Ignition coils are identified by engine bank and cylinder position (bank/position) as follows:
V6
V8
Right hand bank
1/1 1/2 1/3
1/1 1/2 1/3 1/4
Left hand bank
2/1 2/2 2/3
2/1 2/2 2/3 2/4
Engine firing order
V6
1/1....2/1....1/2....2/2....1/3....2/3
V8
1/1....2/1....1/4....1/2....2/2....1/3....2/3....2/4
NOTES
7.2
Student Guide
•
•
•
•
•
•
The spark plug for each cylinder is fired by an on-plug
ignition coil.
The primary current side of each coil is supplied with
ignition switched B+ power.
The ground side of each coil is switched directly by
the PCM with no additional ignition amplifiers
required.
The primary coil switching duration is limited by the
PCM to manage the voltage at 9.0v through the coils.
Damage to the coils will result if the PCM switched
circuit is short circuited to ground.
The ignition suppression capacitors in the B+ supply circuit, fitted to the rear of each cylinder head,
prevent radio interference.
Service Training
ON-PLUG IGNITION COILS – V6
CAUTION: The ignition coils are rated at
approximately 9 volts. Testing a coil by
applying B+ voltage will cause permanent damage and may destroy the unit.
IGNITION SUPPRESSION
CAPACITOR
NOTES
880 PTEC.55
ON-PLUG IGNITION COILS – V8
880 PTEC.56
Student Guide
7.3
Service Training
IGNITION
Ignition Knock (detonation) Control
BANK 1 KNOCK SENSOR – V6
•
•
•
•
880 PTEC.57
•
BANK 2 KNOCK SENSOR: – V6
•
•
•
•
880 PTEC.58
•
The ECM retards ignition timing to individual cylinders to control ignition knock (detonation) and
optimize engine power.
Two knock sensors (KS) are positioned on the cylinder block to sense engine detonation. One KS is
positioned on bank 1 and the other on bank 2.
V6 knock sensors are attached to the engine bank
in different locations.
– the bank 1 sensor, with the short flying lead, is
located on the right side of the engine block
above the starter motor
– the bank 2 sensor, with the long flying lead, is
located near the oil separator on the top of the
cylinder block.
V8 knock sensors are unchanged from previous
Jaguar V8 engines.
Each knock sensor has a piezo electric sensing element to detect broad band (2 – 20 kHz) engine
accelerations.
If detonation is detected, the PCM determines
which cylinder is firing, and retards the ignition
timing for that cylinder only.
If, on the next firing of that cylinder, the detonation reoccurs, the PCM will further retard the ignition timing
If the detonation does not reoccur on the next firing, the PCM will advance the ignition timing
incrementally with each firing.
The knock sensing ignition retard / advance process can continue for a particular cylinder up to a
specified maximum retard measured in degrees of
crankshaft rotation.
During acceleration at critical engine speeds, the
PCM retards the ignition timing to prevent the
onset of detonation. This action occurs independent of input from the knock sensors
NOTES
7.4
Student Guide
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
8.2
Student Guide
Service Training
Service Training
VARIABLE VALVE TIMING / VARIABLE INTAKE
Variable Valve Timing (VVT) – V6
A VVT system is used to allow the phasing of the inlet valve opening to be changed relative to the fixed timing of the
exhaust valves. Two positions are used, 30˚ apart, with the advanced position occurring at 30˚ BTDC and overlapping with the exhaust opening.
The operating strategy is controlled by the engine management system in conjunction with the variable geometry
induction system so as to optimize torque characteristics over the engine speed/load range. The VVT system also
provides increased amounts of ‘internal’ EGR under certain speed/load operating conditions.
TWO-STAGE VVT TIMING – V6
INLET CAMSHAFT RETARDED
INLET CAMSHAFT RETARDED
TDC
TDC
Inlet opens at TDC
Exhaust closes at
11.5˚ ATDC
Exhaust closes at
11.5˚ ATDC
Inlet opens at
30˚ BTDC
11.5˚ overlap
IN
ET
L
Inlet closes at
66˚ ABDC
EXHA
U
EX
41.5˚ overlap
UST
HA
Exhaust opens at
57.5˚ BBDC
ST
IN L
Exhaust opens at
57.5˚ BBDC
ET
Inlet closes at
36˚ ABDC
BDC
BDC
INLET CAMSHAFT
VALVE OVERLAP
EXHAUST CAMSHAFT
880 PTEC.59
NOTES
Student Guide
8.3
Service Training
Variable Valve Timing (VVT) – V6 (continued)
V6 VVT Oil Feed
VVT OIL FEED – V6
•
VVT UNIT
VVT OIL
CONTROL VALVE
•
•
The VVT/sprocket unit is fixed on the nose of each
inlet camshaft via a locating pin and hollow bolt
and is driven directly by the timing chain.
The oil feed to each VVT unit is supplied via fixed
oilways in the cylinder heads
The oil feed is controlled by the VVT solenoid
operated oil control valves, which are bolted
directly to each cylinder head.
880 PTEC.60
NOTES
8.4
Student Guide
Service Training
V6 VVT Operation
From the oil control valve, the flow is via the thrust bearing cap, through drillings in the camshaft and then through
the hollow fixing bolt which secures the VVT unit. Drain holes are provided at the rear (camside) face of the VVT unit
for any residual oil which has seeped past the piston.
With the oil control valve open, oil pressure on the helical drive piston is increased, rotating the cams to the
advanced position. When the valve closes, oil pressure reduces and the return spring pushes the piston back to the
fully retarded position.
The oil control valve is controlled by a 300Hz PWM signal from the PCM which sets it to either the fully open or fully closed position.
TW0-STAGE VVT OPERATION – V6
THRUST BEARING
CAP
VVT UNIT WITH
OIL PRESSURE
VVT
OIL CONTROL VALVE
OPEN
THRUST BEARING
CAP
VVT UNIT WITH
OIL PRESSURE REDUCED
VVT
OIL CONTROL VALVE
CLOSED
880 PTEC.61
Student Guide
8.5
Service Training
Variable Valve Timing – V8
The V8 variable valve timing (VVT) system is the same as the linear VVT system used on AJ27 V8 engines. The system provides continuously variable inlet valve timing over a crankshaft range of 48° ±2°. Depending on driver demand, engine
speed/load conditions and Powertrain Control requirements, the inlet valve timing is advanced or retarded to the optimum angle within this range. Compared to the two position system, inlet valve opening is advanced by an extra 8°,
providing greater overlap and increasing the internal EGR effect (exhaust gases mixing with air in the inlet port).
LINEAR VVT TIMING – V8
EXHAUST
INLET
MAXIMUM ADVANCE
INLET
MAXIMUM RETARD
9
8
VALVE LIFT (mm)
7
6
5
4
3
2
1
0
0
90
180
270
360
450
540
630
720
CRANK ANGLE (degrees)
880 PTEC.62
The linear VVT system provides a number of advantages:
• Improves internal EGR, further reducing NOx emissions and eliminating the need for an external
EGR system
• Optimizes torque over the engine speed range without the compromise of the two position system:
note that specified torque and power figures are unchanged
• Improves idle quality: the inlet valve opens 10° later, reducing valve overlap and thus the internal
EGR effect (undesirable at idle speed)
• Faster VVT response time
• VVT operates at lower oil pressure
NOTES
8.6
Student Guide
Service Training
V8 Linear VVT Components
Each cylinder bank has a VVT unit, bush carrier and solenoid operated oil control valve. The VVT unit consists of an
integral control mechanism with bolted on drive sprockets, the complete assembly being non-serviceable. The unit
is fixed to the front end of the inlet camshaft via a hollow bolt and rotates about the oil feed bush on the bush carrier casting. The bush carrier is aligned to the cylinder head by two hollow spring dowels and secured by three bolts.
The oil control valve fits into the bush carrier to which it is secured by a single screw. The solenoid connector at the top
of the valve protrudes through a hole in the camshaft cover but the cover must first be removed to take out the valve.
Note that only the bush carriers are left and right handed.
LINEAR VVT COMPONENTS – V8
SOLENOID CONNECTOR
OIL CONTROL VALVE
OIL FEED BUSH
BUSH CARRIER
OIL DRAINS
VVT UNIT
OIL FEED
VVT UNIT
FIXING BOLT
880 PTEC.63
NOTES
Student Guide
8.7
Service Training
Variable Valve Timing: – V8 (continued)
V8 Linear VVT unit
LINEAR VVT UNIT – V8
ANTI-BACKLASH
SPRINGS
RETARD CHAMBER
OIL FEED / DRAIN
INNER SLEEVE
The VVT unit drives the secondary chain to the exhaust
camshaft. The inlet camshaft is driven from the body of
the unit via internal helical splines. When commanded
from the PCM, this mechanism rotates the inlet camshaft relative to the body/sprocket assembly to advance
or retard the valve timing.
PISTON RETURN
SPRING
The VVT unit has three main parts:
• the body/sprocket assembly
• an inner sleeve bolted axially to the nose of the
camshaft
• a drive ring/piston assembly located between the
body and inner sleeve and coupled to both via
helical splines.
ADVANCE CHAMBER
OIL FEED / DRAIN
ADVANCE CHAMBER
DRIVE RING
AND PISTON ASSEMBLY
880 PTEC.64
Oil pressure applied in the advance chamber forces the
drive ring/piston assembly to move inwards along its
axis while rotating clockwise on the helical body
splines. Since the drive ring is also helically geared to
the inner sleeve but with opposite angled splines, the
inner sleeve is made to rotate in the same direction,
turning the camshaft.
To move back to a retard position, oil pressure is switched to the retard chamber and the piston and rotational
movements are reversed. A light pressure spring is fitted in the retard chamber to assist the piston assembly to revert
to the fully retarded position with the engine stopped.
NOTES
8.8
Student Guide
Service Training
Linear VVT Oil Control
Engine oil is supplied to the VVT unit via the bush carrier and is switched to either the advance or retard side of the
moving piston assembly by the oil control valve. The oil control valve consists of a four spool shuttle valve directly
operated by a solenoid plunger and fitted with a return spring. It is a non-serviceable component.
To fully advance the cams, the solenoid is energized pushing the shuttle valve down. This action causes the incoming oil feed to be directed through the lower oilway in the bush carrier and into the advance oil chamber where it
pushes on the piston/drive ring assembly. As the piston moves in the advance direction (towards the camshaft), oil is
forced out of the retard chamber through oilways in the sprocket unit, camshaft, hollow fixing bolt, bush carrier and
the shuttle valve from which it drains into the engine.
To move to the fully retarded position, the solenoid is de-energized, the return spring holds the shuttle valve in its
upper position and the oil flow is directed through the bush carrier upper oilway into the VVT unit. Oil is channelled through the hollow VVT fixing bolt and via oilways in the camshaft and sprocket unit to the retard chamber
where it acts on the moveable piston/drive ring assembly. As the piston moves, oil is forced from the advance chamber back through the shuttle valve to the engine.
LINEAR VVT OIL CONTROL – V8
VVT
SOLENOID VALVE
BUSH CARRIER
DRIVE RING AND
PISTON ASSEMBLY
RETARD CHAMBER
VVT UNIT FIXING BOLT
CAMSHAFT
ROTATION
TO RETARD
OIL FEED
OIL DRAINS
FOUR-SPOOL
SHUTTLE VALVE
CAMSHAFT
OIL DRAINS
CAMSHAFT
ROTATION
TO ADVANCE
OIL FEED
880 PTEC.65
Student Guide
8.9
Service Training
Variable Valve Timing – V8 (continued)
Linear VVT-PCM Control System
Closed loop control
Normally, continuously variable timing requires the VVT piston to be set to the optimal position between full
advance and retard for a particular engine speed and load. The PCM positions the shuttle valve using a PWM control signal operating at a frequency of 300 Hz. The shuttle valve assumes a position between the limits of travel
proportional to the “duty cycle” of the signal. An increasing duty cycle causes an increase in timing advance.
The actual position of the camshaft is monitored by the PCM from the CMP sensor signal. If a difference is sensed
between the actual and demanded positions, the PCM will attempt to correct it.
Engine oil temperature
Engine oil properties and temperature can affect the ability of the VVT mechanism to follow demand changes to the
cam phase angle. At very low oil temperatures, movement of the VVT mechanism is sluggish due to increased viscosity and at high temperatures the reduced viscosity may impair operation if the oil pressure is too low.
The VVT system is normally under closed loop control except in extreme temperature conditions such as cold starts
below 0 °C (32 °F). At extremely high oil temperatures, the PCM may limit the amount of VVT advance to prevent
the engine stalling when returning to idle speed. This could occur because of the slow response of the VVT unit to
follow a rapid demand for speed reduction. Excessive cam advance at very light loads produces high levels of internal EGR which may result in unstable combustion or misfires.
NOTES
8.10
Student Guide
Variable Intake System (V6)
Service Training
VARIABLE INTAKE SYSTEM MANIFOLD (V6)
V6 engines use a variable intake system designed to
optimize engine torque across the engine speed / load
range. Variable intake combined with variable valve
timing provides an optimized engine torque curve
throughout the engine operating range.
TOP IMT VALVE
BOTTOM IMT VALVE
Variable Intake Components
•
•
•
•
•
•
•
•
•
•
The throttle body connects directly to the induction
manifold assembly, which is constructed of aluminum alloy.
The manifold mounts to the cylinder heads with the
lower intake manifold assembly “sandwiched”
between.
The manifold plenum chamber is split into upper and
lower compartments with two interconnecting holes.
Two identical Intake Manifold Tuning (IMT) Valves
are located at the interconnecting holes.
The IMT valves are solenoid operated gate valves,
which rotate 90° for open / close.
B+ voltage is separately supplied to each IMT valve
via powertrain control relay 1 in the front power distribution box.
The PCM switches the ground side of the valves via
separate hard wires to activate the solenoids.
The plenum chamber volume and the length of the
intake air path are tuned by the positions of the IMT
valve gates to assure that the natural charge air pres880 PTEC.66
sure waves or pulses are maximized for the everchanging engine speed and load conditions.
The plenum chamber volume and manifold geometry can be set to three different configurations based on the
specific engine speed / load range:
– short pipe
– medium-length pipe
– long pipe
The two IMT valves, controlled by the PCM are set in combination to provide the three manifold configurations.
NOTES
Student Guide
8.11
Service Training
Variable Intake System (V6) (continued)
VARIABLE INTAKE SYSTEM OPERATION (V6)
BOTH IMT VALVES CLOSED
TOP IMT VALVE OPEN / BOTTOM IMT VALVE CLOSED
BOTH IMT VALVES OPEN
880 PTEC.68
8.12
Student Guide
Service Training
The PCM calculates the required valve positions using the following data:
• Engine speed from CKP sensor
• Throttle position from TP sensors
• Engine temperature from CHT sensor
• Charge air temperature from IAT sensor
Both valves closed
Both IMT valves closed provides the minimum plenum volume and the shortest intake air path to the cylinders.
Top valve open / bottom valve closed
With the top valve open and the bottom valve closed, plenum volume and the effective length of the intake air path
are both increased.
Both valves open
With both valves open, the plenum volume and the air intake path effective length are at their maximum.
The graph shows the how the PCM control of variable intake system optimizes the engine torque curve.
ENGINE TORQUE CHARACTERISTICS
325
300
BRAKE TORQUE (Nm)
275
250
225
200
CLOSED
OPEN
CLOSED
TOP IMT VALVE
175
CLOSED
OPEN
CLOSED
BOTTOM IMT VALVE
150
ADVANCED
RETARDED
VVT
125
1000
2000
3000
4000
5000
6000
7000
ENGINE SPEED (rpm)
880 PTEC.67
NOTES
Student Guide
8.13
8.14
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
Service Training
EXHAUST GAS RECIRCULATION (EGR): V6 ONLY
The EGR system is only fitted to V6 engines and comprises the following components:
• EGR vacuum regulator valve
• EGR valve
• Differential pressure feedback EGR sensor
• Exhaust gas feedback pipe with internal orifice
Exhaust gas is recirculated back to the engine intake in proportion to a measured pressure differential in the feedback pipe. The amount of gas recirculated varies primarily with engine speed and load but is also modified by the
PCM to allow for other factors, e.g. coolant temperature, and also to achieve optimum emissions and fuel economy.
The recirculated exhaust gas is taken from the bank 1 exhaust manifold and fed into the engine via the EGR valve.
The feedback pipe contains an internal tube with a small diameter orifice that creates a pressure differential in the
feedback pipe. Two small pipes, connected to the feedback pipe each side of the orifice, transmit the pressure differential to the differential pressure feedback EGR sensor.
EGR SYSTEM (V6)
EGR VALVE
EGR VACUUM
REGULATOR VALVE
DPFE SENSOR
EXHAUST GAS
FLOW
ORIFICE
880 PTEC.70
NOTES
9.2
Student Guide
Service Training
Differential pressure feedback EGR (DPFE) sensor
The PCM receives an EGR feedback signal from the DPFE sensor. The sensor consists of a vacuum operated variable
capacitor and a processing circuit, which convert the input pressure / vacuum value to a corresponding analogue
voltage signal. The DPFE sensor has a linear response and the variations in exhaust pressure produce a signal voltage in the range of 1V – 3.5V dc.
•
•
•
•
The EGR vacuum regulator valve and the EGR valve
comprise the actuating components of the control
loop.
The EGR vacuum regulator valve has a vacuum input
from the manifold distribution pipes, a vacuum output to the EGR valve, and receives a pulse width
modulated (PWM) signal from the PCM.
The PWM signal switches the vacuum control output
to the EGR valve according to input demand from the
differential pressure feedback EGR sensor or in
response to override conditions determined by the
engine management system.
The EGR valve is a vacuum operated diaphragm
valve with no electrical connections, which opens
the EGR feed pipe to the induction manifold under
the EGR vacuum regulator control.
DPFE SENSOR (V6)
880 PTEC.69
EGR Control Conditions
EGR operates over most of the engine speed/load range but is disabled by the engine management system under certain conditions:
• During engine cranking
• Until normal operating temperature is reached
• When the diagnostic system registers a failure which affects the EGR system (e.g. a faulty sensor)
• During idling to avoid unstable or erratic running
• During wide open throttle operation
• When traction control is operative.
While the main control loop is based on feedback from the differential pressure feedback EGR sensor, the EGR rate is
also modified by other engine conditions; coolant, ambient and charge air temperatures, barometric pressure, VVT
cam position and charge air mass. Note also that the EGR rate increases gradually after it is enabled during each driving period.
NOTES
Student Guide
9.3
9.4
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
10.2
Student Guide
Service Training
Service Training
OTHER PCM ENGINE CONTROL AND INTERFACE FUNCTIONS
Radiator Cooling Fan and Air Conditioning Compressor Control
The Jaguar S-TYPE radiator cooling fan is driven by a
variable speed 500W electric motor. An electronic
cooling fan module, located under the radiator cooling
pack, drives the fan motor.
JAGUAR S-TYPE RADIATOR COOLING FAN ASSEMBLY
The cooling fan module is supplied with:
• ignition switched 20 Amp fused B+ power supply
from powertrain relay 1 for the control circuit
• battery direct B+ power supply via the 80 Amp
fuse adjacent to the front power distribution box
for fan motor drive.
When the engine is running, the cooling fan module
receives a PWM control signal proportional to the
engine cooling requirements from the PCM. In
response to the PCM control signal, the cooling fan
module switches the fan motor ON and OFF and varies
fan speed between 300 rpm to 2900 rpm using PWM
drive voltage.
COOLING FAN MODULE
880 PTEC.71
As the engine is switched off, the A/CCM notes the engine coolant (V8) or cylinder head (V6) temperature
(SCP MESSAGE) and provides a control signal to the cooling fan control module for a fixed period of time to operate
the fan motor. The engine off fan operational time period is determined by the A/CCM based on the SCP temperature message.
In addition to radiator cooling fan control, the PCM controls the operation of the air conditioning compressor
clutch. The PCM receives the air conditioning compressor operation request from the A/CCM via the SCP network.
The PCM calculates the engine cooling requirement from signal inputs received from the following sources:
• ECT sensor (V8)
• CHT sensor (V6)
• Air conditioning pressure sensor
• Air conditioning compressor status
• Transmission fluid temperature
NOTES
Student Guide
10.3
Service Training
OTHER PCM ENGINE CONTROL AND INTERFACE FUNCTIONS
Radiator Cooling Fan and Air Conditioning Compressor Control (continued)
Air Conditioning Pressure Sensor
The air conditioning pressure sensor, located in the A/C “high side” is a pressure transducer sensing refrigerant system
high side pressure. The feedback voltage from the transducer supplies the PCM with a signal proportional to refrigerant
pressure. The PCM uses the refrigerant pressure signal for coolant fan requirement and compressor clutch control.
Fail Safe Engine Cooling (V6)
V6 PCMs are programmed with a function that monitors engine temperature and performs actions that prolong safe
engine operation by controlling engine temperature. This “fail safe engine cooling” strategy is fully controlled by the
PCM. Fail safe engine cooling strategy on V6 engines is made possible by monitoring the engine temperature with a
cylinder head temperature (CHT) sensor (metal contact) instead of a ECT sensor (coolant).
If the PCM detects excessively high engine temperature, it switches off the fuel injector(s) of one or more cylinders.
With no fuel being injected, ambient air is pumped through the cylinder cooling the engine. By switching individual
injectors off for a period of time and in a sequence determined by the PCM, engine temperature can be controlled to
allow the vehicle to be driven for a short distance.
The overall engine cooling strategy can be divided into five stages. The fail safe engine cooling (FSC) strategy operates in the three top stages as explained in the following chart.
Engine cooling strategy
Stage
Temperature
Warnings
Action
Normal
82 °C (180 °F) – 118 °C (245 °F)
Coolant temp gauge
Normal cooling fan control
> 118 °C (245 °F) – <121 °C (250 °F)
Coolant temp gauge in RED zone
ENGINE OVERTEMP warning light
CHECK ENGINE TEMP message
Single chime
Cooling fan maximum
> 121 °C (250 °F) – < 149 °C (300 °F)
REDUCED ENGINE POWER message
CHECK ENGINE MIL
Three chimes
Cooling fan maximum
PCM begins selectively and
alternately shutting off the
fuel injectors
Engine speed limited
FSC Stage 2
Stop engine safely
> 149 °C (300 °F) – < 166 °C (330 °F)
Flashing ENGINE OVERTEMP
warning light
STOP ENGINE SAFELY message
CHECK ENGINE MIL
Five chimes
Cooling fan maximum
PCM continues selectively
and alternately shutting
off the fuel injectors
Engine speed limited
FSC Stage 3
Engine shut down
166 °C (330 °F)
CHECK ENGINE MIL
Cooling fan maximum
PCM shuts down engine
Above normal
FSC Stage 1
Reduced power
All temperatures shown are approximate.
10.4
Student Guide
Service Training
Generator
The PCM is responsible for issuing SCP commands directing the instrument pack to switch the generator warning
light OFF or ON. Each time the ignition is switched ON to position II, the instrument pack initiates its bulb check
cycle. The generator warning light will remain active until the instrument pack receives an SCP LOW VOLTAGE
TELLTALE (OFF) message from the PCM.
The PCM receives generator charging voltage information via a hard wire from generator pin marked ALTLMP on
the generator. If the charging system is functioning correctly, the PCM transmits the SCP LOW VOLTAGE TELLTALE
(OFF) message. If the PCM detects an out of range voltage (high or low) during normal operation, it transmits an SCP
LOW VOLTAGE TELLTALE (ON) message signaling the instrument pack to activate the generator warning light. If
the generator detects an internal fault it holds the ALTLMP signal at zero volts. After 15 seconds at zero volts the
PCM transmits the SCP LOW VOLTAGE TELLTALE (ON) message and triggers a non OBD II DTC.
The PCM receives generator load information via a hard wire from the generator pin marked FRI. This circuit communicates a PWM signal proportional to generator field load. When the vehicle battery is fully charged and
electrical demands are low, generator output can drop to zero resulting in a B+ voltage signal. As generator output
increases to supply increased electrical demands the PWM duty cycle increases. At full generator output the duty
cycle is 100% resulting in a continuous zero voltage signal. The PCM increases throttle valve opening at idle to compensate for the increased generator load.
NOTES
Student Guide
10.5
10.6
Student Guide
Service Training
J A G U A R
S E R V I C E
T R A I N I N G
PTEC ENGINE
MANAGEMENT SYSTEM
1
PTEC OVERVIEW AND
CONTROL SUMMARY
2
3
4
INDUCTION AIR AND
THROTTLE CONTROL
5
FUEL DELIVERY AND
6
FUEL INJECTION
7
IGNITION
8
VARIABLE INTAKE
9
V6 ONLY
INTERFACE FUNCTIONS
11 TASK SHEETS
z
Service Training
S-TYPE - DTC Summaries
1. What is KOEO self test?
2. What is KOER self test?
3. What does DTC P1001 provide as a fault description?
4. If DTC P0102 is logged what self test should you perform? KOEO [ ], KOER [ ], Why?
5. Elaborate on DTC P1299.
• Can it be logged on an AJ V8 PTEC system: Yes [ ] No [ ]
• How many trips does it require to log? 1 Trip [ ], 2 Trips [ ]
• What is the PCM’s default action if this fault is logged?
•Will any messages be displayed in the Instrument Cluster with this DTC: Yes [ ] No [ ]
•If “Yes” please list the messages.
6. Is the drive cycle for comprehensive component monitoring longer for the AJV8 compared to the AJV6? Yes [ ] No [ ]. If yes, why?
Instructor Check:
Student Workbook
880 Worksheet.fm
z
Service Training
S-TYPE - PTEC Overview
1. Review the correct Electrical Guide and list the power distribution paths for the PCM.
2. How does the PCM control power to operate high amperage consumers (i.e.:, AC compressor).
3. Why is communication occurring between the PCM and the Throttle Motor Actuator.
4. What signal does the PCM receive when the PSP switch closes? _____________________
5. Where does APP2 receive it’s operating voltage from? _______________________,
Why? _______________________________________________________________________
Student Workbook
880 Worksheet.fm
z
Service Training
S-TYPE - PTEC Fuel Pump Control
1. The illustration below Identifies the components and signals used to operate the fuel
pump. What is the purpose of the IP sensor? ___________________________
2. What is the purpose of the FTS? _____________________________________________
Use the appropriate Electrical Guide to identify the wire colors and pin numbers at the RECM.
3. What type of signal is provided to the RECM by the PCM requesting for fuel pump
operation. ______________, What is the wire color and pin number_________________
4. Signal frequency?_______________. Is it fixed [ ] Yes, [ ] No
5. Signal duty cycle at idle = _____________, under load (2500 RPM) _____________
6. What type of signal is provided from the RECM to drive the fuel pump? ____________,
What is the wire color and pin number. ___________________________________
7. Signal frequency ? ______________. Is it fixed [ ] Yes, [ ] No
8. Signal duty cycle at idle = _____________, under load (2500 RPM) _____________
9. Load PDU multimeter, load amp clamp. Connect the fuel pump control circuit and
measure value. Record reading at the idle and under load.
Idle = __________
Under load = ___________
Instructor Check: __________________________
Student Workbook
880 Worksheet.fm
z
Service Training
S-TYPE - PCM Datalogger
Name:_______________________, Date:____________, Vehicle/VIN__________________
Connect the PTU to the vehicle and enter the datalogger program.
1. With the engine running, highlight the information button on each signal. Observe and
record the following signals.
•AIRI = Air Assist Injection ____________________________________________________
•CHT = Cylinder Head Temperature sensor (AJV6) ________________________________
•DPFE V6 =Differential Pressure Sensor ________________________________________
•EFPT = Fuel Rail Pressure Transducer __________________________________________
•EFT = Fuel Rail Temperature Sensor ____________________________________________
•FPDC = Fuel Pump Duty Cycle. _______________________________________________
•EGRDC = EGR Duty Cycle ____________________________________________________
•H02SIU = Upstream 02 Sensor Signal __________________________________________
•H02SID = Downstream 02 Sensor Signal _______________________________________
•MAF= Mass Air Flow ________________________________________________________
•PURGEDC = Purge Valve Duty Cycle ___________________________________________
2. Monitor and record the following signals with engine at idle and then at 1500 RPM.
•APP1 = ____________________________________________________________________
•APP2 = ____________________________________________________________________
•APP3 = ____________________________________________________________________
•TPS1 = ____________________________________________________________________
•TPS2 = ____________________________________________________________________
•TPS3 = ____________________________________________________________________
Instructor Check:
Student Workbook
880 Worksheet.fm
PTEC V8 ENGINE MANAGEMENT, PART 1 – 2001 MY S-TYPE
SCP
20.1
PI1-05
PI1-08
WR
I
O
PI1-10
PI1-50
S
PI1-15
20.1
O
PI1-18
S
O
PI1-19
D
I
PI1-25
O
PI1-29
O
PI1-33
O
PI1-37
I
PI1-39
I
PI1-40
FH1-04
20.2
YG
FH1-13
66
GY
B+
P
67
FH1-32
GO
B+
P
05.1
FH1-33
O
FH1-40
PI1-43
NOTE:
ON VEHICLES WITH DYNAMIC STABILITY
CONTROL, THE PCM RECEIVES THE
BRAKE ON / OFF SIGNAL (FH1-40) FROM
THE DSC CONTROL MODULE.
SP
D
WU
PI1-45
I
PI1-47
PI1-48
FH1-49
17.1
PI1-44
I
I
I
PI1-49
I
PI1-51
I
PI1-52
I
PI1-53
I
PI1-54
I
PI1-55
FH1-47
PI1-56
I
PI1-57
I
PI1-58
I
PI1-59
I
FH1-01
NR
NR
CV1-2
ILS2
IL10-11
75
IL10-10
-1
IL10-4
FP1 -3
74
76
P
77
P
IL10-12
FP2 -3
73
P
-2
P
-2
FH13 -7
FH13-16
-1
YP
CV4 -2
-1
WP
SR
-1 PI48 -2
-1
GR
-1 PI27 -2
WB
SB
GW
WP
GO
WB
-1 PI47 -2
PI40 -2
PI26 -2
NW
-2
BO
PI4 -1
GB
-2
NG
PI5 -1
GO
-2
NY
-1
WR
-2 PI10
-1
SR
PI11
WR
-1
NY
NG
WG
N
GY
N
W
GU
NR
NR
WR
NG
WG
GB
NG
-2
PIS6
-6
-17
-3
PIS2
PIS1
-4
-5
FH68 -1
-2
MAF
SENSOR
IAT
SENSOR
PI51 -2
-1
-1
FH3 -2
-1
CA88
-9
-5
-10
-6
-4
-8
-2
PI16 -4
-7
BRAKE
SWITCH
PSP
SWITCH
EVAP CANISTER
PURGE VALVE
APP2
APP SENSOR
-10
-1
-2
-3
-6
20.1
-9
-2
-3
GY
U
S
S
S
W
-12
-10
-4
-5
APP3
FH49
H
H
H
TP1
TP2
TP3
TP SENSOR
5
2
3
1
-6
GY
20.1
B
PI44 -6
S
-3
P
APP1
-7
B
-7
N
-1
Y
-3
-6
W
-2
-5
WR
-8
B
B
CA37 -2
υ
*NOTE:
EVAP CANISTER CLOSE VALVE AND FUEL TANK
PRESSURE SENSOR – OBD II VEHICLES ONLY.
FH49
-2
-9
-8
BY
FH20 -3
-4
PI2
RY
B
B
FH5
-5
GY
PI46-1
P
-7
FHS32
GR
POWERTRAIN
CONTROL MODULE
64
P
BW
PI2
71
W
PI2-1
70
N
FH1-55
Y
FH1-52
YU
I
I
GY
4
-11
YU
I
FH1-43
WU
FH1-51
CAS29
WU
I
OY
FH13-14
NR
I
OY
FHS1
NR
FH1-40
Y
FH1-27
I
Y
FH1-26
I
OG
FH1-25
OU
FH1-24
GY
SCP
WR
FH1-38
WR
FH1-37
I
NR
FH1-31
I
NW
B
B
B
B
NY
I
A/C PRESSURE
SENSOR
FHS4
NR
FH1-23
03.4
FHS3
YR
O
FH1-22
YR
FH1-20
W
FH1-17
W
FH1-16
N
FH1-15
I
N
FH1-12
I
GU
FH1-10
O
NR
FH1-06
N
O
YP
W
FH1-05
WR
N
NU
NR
NR
W
WU
N
Y
BY
YR
WU
W
NU
O
WP
WP
YU
WP
AIR BAG SYSTEM –
AIR BAG DEPLOYMENT
(CIRCUIT CONTINUED)
20.2
I
IL2 -3
-2
P
GR
SERIAL
COMMUNICATION
PI1-42
I
IL9 -1
P
P
WU
DSC CM –
BRAKE ON / OFF
PI1-20
-2
WB
-2 PI13 -1
83
P
N
NR
WB
N
N
S
S
YB
W
NY
WP
NG
WG
WP
SB
SR
WR
W
WU
Y
WG
WB
WR
WP
WB
SR
WR
W
W
WR
-1
80
P
NU
PCM FLASH
PROGRAMMING
-2
81
B
SCP
PI1-17
S
FH1-03
U
-3
YP
O
PI6 -4
NW
PI1-07
-1
υ
WP
O
-2
2
YP
02.1
I
-3
1
2
FTP
SENSOR*
NW
GENERATOR
LOAD
SR
PI7 -4
KS
YG
02.1
-3
GBS2
82
GENERATOR
WARNING
-4
1
KS
EVAP
CANISTER
CLOSE
VALVE*
IMT
IMT
VALVE
CKP
VALVE
SENSOR (BOTTOM) (TOP)
WP
I
GB1-29
-1
VVT
VALVE
NU
GB1-28
GB4 -2
VVT
VALVE
NU
GB1-17
I
NU
NG
N
WU
WG
-3
NU
GB1-16
-4
WU
GB1-15
O
GR
O
-1
υ
NW
υ
λ
PI12 -1
GB3 -2
CMP
SENSOR
2
WP
λ
YG
λ
CMP
SENSOR
1
NG
λ
2/1
WG
SCP NOTE:
THE PCM COMMUNICATES WITH
THE THROTTLE ACTUATOR CONTROL MODULE
ONLY FOR DIAGNOSTIC PURPOSES.
1/1
IP
SENSOR
NU
2/2
EOT
EFT
CHT
SENSOR SENSOR SENSOR
WU
1/2
HO2
SENSOR
NW
HO2
SENSOR
HO2
SENSOR
WP
HO2
SENSOR
S
#4
85
THROTTLE ACTUATOR CONTROL MODULE
THROTTLE ASSEMBLY
86
THROTTLE MOTOR
CONTROL RELAY
FRONT POWER
DISTRIBUTION BOX
FUEL INJECTORS
GO
GB
GR
GU
GY
GW
GU
GR
ILS1
-2
PI34 -1
-2
IGNITION
SUPPRESSION
CAPACITOR
GW
PI33 -1
NW
-2
GO
PI32 -1
-2
NY
PI31 -1
2/3
2/2
GB
-2
NG
PI29 -1
2/1
GR
-2
NU
PI28 -1
1/3
GU
-2
NR
IL8 -1
GY
-2
N
IL7 -1
1/2
1/1
GO
-2
BR
IL6 -1
2/3
GB
-2
GR
BU
IL5 -1
BO
-2
IGNITION COILS
2/2
2/1
BG
1/3
GY
IL4 -1
BY
-2
GW
BW
IL3 -1
1/2
GU
1/1
69
P
IL10-6
GU
GW
GO
GB
GR
GU
GY
PI37
GB
84
PIS7
P
GU
PI38
IL10-1
GY
66
B+
P
FH1-32
GO
67
B+
P
FH1-33
20.1
S
S
FH1-03
SCP
20.1
U
S
FH1-04
O
PI1-02
O
PI1-11
O
PI1-12
O
PI1-13
O
PI1-14
O
PI1-21
O
PI1-22
O
PI1-23
O
PI1-24
O
PI1-30
O
PI1-31
O
PI1-32
O
FH1-09
FH1-17
FH1-20
I
FH1-24
I
FH1-25
I
FH1-26
I
FH1-27
I
FH1-28
O
FH1-36
I
FH1-42
I
FH1-43
FH1-56
I
FH1-57
O
FH1-58
IL10-7
IL10-2
IL10-8
IL10-3
IGNITION
SUPPRESSION
CAPACITOR
IL10-9
NW
NG
NG
NU
N
NY
NY
NR
NR
NW
N
NU
AIR CONDITIONING
COMPRESSOR CLUTCH
RELAY
4
03.3
MULTIPLE CIRCUITS
AND WIRE COLOR CODES
03.3
NU
N
Y
B
B
B
B
OY
NY
WP
NY
BO
YU
WP
5
3
RO
NU
2
1
GR
FHS4
B
B
PI46-8
B
PIS8
GY
PI41-2
PI41-1
FRONT
POWER DISTRIBUTION BOX
PI46-11
AIR CONDITIONING
COMPRESSOR CLUTCH
FH42
(FH22)
NY
GO
68
BO
FC5-4
BO
BY
FCS6
CS2-8
OFF
BO
CS5-4
CANCEL
SET -
SET + RESUME
P
ON
SQ2-3
CASSETTE
FC3-3 (LHD)
FC5-9 (RHD)
FH49
YU
RB
CS2-7
120 Ω
SQ2-1
CASSETTE
180 Ω
300 Ω
510 Ω
1κ Ω
B+ (FAN)
CF5-3
WB
FC3-11
CS5-6
B+
CF5-6
5
YU
I
CF5-5
CF1-5
I
CF5-7
CF1-6
2.2κ Ω
BY
CF6-1
O
CF5-1
CF6-2
STEERING WHEEL
COOLING FAN
20.1
UY
BR
S
O
FC28-04
O
CF5-4
S
FC28-12
COMPRESSOR
CLUTCH REQUEST
RY
FH28-17
SB
WB
BR
CF2
I
CF5-2
FC28-01
AIR CONDITIONING
CONTROL MODULE
WP
11
GB
B+
B+
CA101-01
GR
4
FH13-8 (LHD)
FH28-8 (RHD)
GR
CA100-08
O
20.1
SW
CA101-11
GO
GO
FP4-1
FP2-4
S
CA102-01
20.1
UO
S
O
CA101-12
BR
BR
FP2-1
CA102-02
SCP NOTE:
THE RECM ONLY FOR DIAGNOSTIC
PURPOSES.
B (LHD)
BU (RHD)
#7
5
3
2
1
R (LHD)
RU (RHD)
CA101-02
B
CAS57
CA156
REAR ELECTRONIC
CONTROL MODULE
CA36 -2
-1
FH6 -3
-2
-1
GU
FP4-3
GW
FUEL PUMP
CA61-G1
CA116
CA61-G2
12
FUEL PUMP DIODE (2)
BRD
I
19
NW
CA103-19
YP
I
FH95
WP
B+
CA101-03
FUEL PUMP
RELAY
OY
OB
COOLING FAN
MODULE
65
OY
59
78
P
WB
20.1
67
FHS3
YU
POWERTRAIN
CONTROL MODULE
#8
GY
REAR
BRAKE
CANCEL
SWITCH
AIR CONDITIONING
PRESSURE SENSOR
O
PI1-07
O
PI1-08
O
PI1-09
O
PI1-10
82
YG
D
FH1-13
66
GY
B+
P
67
GO
05.1
PI1-17
B+
P
DSC CM –
BRAKE ON / OFF
FH1-33
O
NOTE:
ON VEHICLES WITH DYNAMIC STABILITY
CONTROL, THE PCM RECEIVES THE
BRAKE ON / OFF SIGNAL (FH1-40)
FROM THE DSC CONTROL MODULE.
17.1
SERIAL
COMMUNICATION
20.2
O
PI1-18
O
PI1-19
PI1-20
I
FH1-40
AIR BAG SYSTEM –
AIR BAG DEPLOYMENT
(CIRCUIT CONTINUED)
PI1-15
FH1-32
I
PI1-25
O
PI1-33
I
PI1-39
PI1-42
PI1-43
WU
I
PI1-44
I
PI1-45
I
PI1-46
I
I
PI1-47
D
I
PI1-49
I
PI1-51
I
PI1-52
I
PI1-53
I
PI1-54
I
PI1-55
FH1-47
SP
PI1-48
FH1-49
PI1-56
I
PI1-57
I
PI1-58
I
PI1-59
I
FH1-01
CV4 -2
-1
-1
FP1 -3
GR
WP
-1
BO
WB
SB
GW
WP
-1 PI27 -2
CV1
-2
80
P
PIS6
76
75
P
FP2 -3
74
P
73
P
P
-2
P
FH13
-16
-1
YP
PI40 -2
PI26 -2
NW
-2
WR
PI4 -1
SR
-2
WR
PI5 -1
GO
NY
-1
-1
WB
-2 PI10 -2
SR
PI18 -2
-1
GY
-2
N
PI15 -3
NW
-2
PI11 -1
NG
N
GY
N
W
GU
NR
NR
PI9 -1
-2
FH13 -7
WP
20.2
-2
83
P
N
NR
N
WB
N
N
S
S
YB
W
WP
WG
SB
SR
WR
W
W
WU
Y
WG
WB
WR
WB
WP
SR
WR
W
W
WR
-2 PI39 -1
-6
-17
-3
NU
FH1-04
PCM FLASH
PROGRAMMING
881
-1
υ
YP
S
-2
P
FH1-03
U
-3
2
YP
GB1-29
PI6 -4
FTP
SENSOR*
NW
I
GBS1
-1
1
2
CKP
SENSOR
KS
NW
S
-2
1
KS
WP
GB1-28
-3
VVT
VALVE
EVAP
CANISTER
CLOSE
VALVE*
NU
S
I
WR
20.1
GB1-17
I
PI1-50
NU
NG
N
WU
WG
PI7 -4
-3
NG
SCP
GB1-16
-4
WG
20.1
GB1-15
O
-1
GB
SCP
WR
O
GB4 -2
NG
02.1
I
PI1-05
-3
NU
GENERATOR
LOAD
SR
-4
WU
02.1
GR
GENERATOR
WARNING
-1
WG
PI12 -1
GB3 -2
υ
VVT
VALVE
AAI
VALVE
CMP
SENSOR
2
WP
υ
λ
CMP
SENSOR
1
WB
λ
IP
SENSOR
YG
λ
EFT
SENSOR
NG
λ
SCP NOTE:
THE THROTTLE ACTUATOR CONTROL MODULE
ONLY FOR DIAGNOSTIC PURPOSES.
EOT
ECT
SENSOR SENSOR
2/1
WG
1/1
NU
2/2
HO2
SENSOR
WU
1/2
HO2
SENSOR
N
HO2
SENSOR
W
HO2
SENSOR
PIS2
PIS1
FH68 -1
-2
CA37 -2
PI50 -2
-1
υ
-1
FH3 -2
-9
-5
-10
-6
-4
-8
-2
PI16 -4
-7
-10
-1
-2
-3
-6
20.1
-12
-9
-2
GY
U
S
-3
-10
-4
-5
-7
S
-3
-1
H
H
H
TP1
TP2
TP3
4
-11
S
APP1
MAF
SENSOR
IAT
SENSOR
BRAKE
SWITCH
PSP
SWITCH
EVAP CANISTER
PURGE VALVE
APP2
APP SENSOR
APP3
FH49
TP SENSOR
2
3
1
#4
85
P
FH49
*NOTE:
EVAP CANISTER CLOSE VALVE AND FUEL TANK
PRESSURE SENSOR – OBD II VEHICLES ONLY.
5
-6
GY
20.1
B
PI44 -6
S
-15
S
-9
W
-11
B
-14
-8
BY
-2
-10
PI2
RY
-5
-13
-16
-5
GY
-4
-1
BY
B
N
OG
OU
NW
WP
GR
WU
NU
CA88
FH20 -3
-12
N
FH5
YR
P
-7
GR
B
B
64
P
PI46-1
B
POWERTRAIN
CONTROL MODULE
(CONTINUED FIGURE 03.3)
PI2
71
PI2-1
W
70
Y
B
W
FH1-43
WR
FH1-55
CAS29
FH13-14
W
I
FHS1
N
FH1-52
Y
FH1-51
I
YU
I
I
OY
SCP
YU
I
FHS32
OY
GU
FH1-27
FH1-40
NR
FH1-26
I
N
FH1-25
I
GY
FHS3
WU
FH1-38
I
FH1-24
A/C PRESSURE
SENSOR
GY
NR
FH1-37
W
B
B
B
B
NY
FH1-31
I
WU
FH1-23
I
03.2
FHS4
NR
FH1-22
Y
FH1-20
O
Y
FH1-17
WR
FH1-16
WR
FH1-15
I
NR
FH1-12
I
NR
FH1-10
O
YR
FH1-06
W
O
YP
N
FH1-05
WR
N
NU
NR
NR
W
WU
N
Y
BY
YR
WU
W
NU
O
WP
WP
YU
THROTTLE ACTUATOR CONTROL MODULE
THROTTLE ASSEMBLY
86
THROTTLE MOTOR
CONTROL RELAY
FRONT POWER
DISTRIBUTION BOX
FUEL INJECTORS
GY
GW
GO
GB
GR
GU
GY
GW
GY
66
B+
P
FH1-32
GO
67
B+
P
FH1-33
20.1
S
S
FH1-03
SCP
20.1
U
S
FH1-04
O
PI1-01
O
PI1-02
O
PI1-11
O
PI1-12
O
PI1-13
O
PI1-14
O
PI1-21
O
PI1-22
O
PI1-23
O
PI1-24
O
PI1-29
O
PI1-30
O
PI1-31
O
PI1-32
O
PI1-37
O
PI1-38
O
FH1-09
FH1-17
FH1-20
I
FH1-24
I
FH1-25
I
FH1-26
I
FH1-27
I
FH1-28
O
FH1-36
I
FH1-42
I
FH1-43
FH1-56
I
FH1-57
O
FH1-58
PI36 -1
-2
N
PIS10
GU
GR
69
P
PIS9
BANK 2
IGNITION
SUPPRESSION
CAPACITOR
GU
GY
GW
GO
GB
GR
GU
GY
GU
PI37
PIS5
GR
GB
84
P
PIS7
GU
NR
NW
NG
NW
NG
N
NY
NU
NY
NR
NW
N
N
NU
N
NR
PI38
BANK 1
IGNITION
SUPPRESSION
CAPACITOR
AIR CONDITIONING
COMPRESSOR CLUTCH
RELAY
03.1
MULTIPLE CIRCUITS
AND WIRE COLOR CODES
4
03.1
NU
N
Y
B
B
B
B
OY
NY
WP
NY
BO
YU
WP
#8
GY
5
3
RO
NU
2
1
GR
FHS4
B
B
PI46-8
GY
PI41-2
PI41-1
FRONT
PI46-11
AIR CONDITIONING
COMPRESSOR CLUTCH
FH42
(FH22)
NY
GO
68
BO
FC5-4
BO
BY
FCS6
CS2-8
OFF
BO
CS5-4
CASSETTE
CANCEL
SET -
SET +
RESUME
P
ON
SQ2-3
FC3-3 (LHD)
FC5-9 (RHD)
FH49
YU
CS2-7
CS5-6
CASSETTE
RB
120 Ω
180 Ω
300 Ω
510 Ω
1κ Ω
B+ (FAN)
CF5-3
WB
FC3-11
SQ2-1
B+
CF5-6
5
YU
I
CF5-5
CF1-5
I
CF5-7
CF1-6
2.2κ Ω
BY
CF6-1
O
CF5-1
CF6-2
STEERING WHEEL
COOLING FAN
SB
20.1
UY
RY
FH28-17
BR
S
O
FC28-04
O
CF5-4
S
FC28-12
COMPRESSOR
CLUTCH REQUEST
WB
BR
CF2
I
CF5-2
FC28-01
FH95
AIR CONDITIONING
CONTROL MODULE
WP
B+
B+
CA101-01
GR
CA101-11
GO
CA101-03
11
GB
FUEL PUMP
RELAY
4
FH13-8 (LHD)
FH28-8 (RHD)
CA100-08
O
20.1
SW
GO
FP2-4
S
FP4-1
CA102-01
20.1
UO
S
O
CA101-12
BR
BR
FP2-1
CA102-02
SCP NOTE:
THE RECM ONLY FOR DIAGNOSTIC
PURPOSES.
#7
GR
5
3
B (LHD)
BU (RHD)
2
1
R (LHD)
RU (RHD)
CA101-02
B
CAS57
CA156
REAR ELECTRONIC
CONTROL MODULE
CA36 -2
-1
FH6 -3
-2
-1
GU
FP4-3
GW
FUEL PUMP
CA61-G1
CA61-G2
12
CA116
FUEL PUMP DIODE (2)
BRD
I
19
NW
CA103-19
YP
I
WP
B+
OY
OB
65
OY
59
78
P
WB
20.1
67
FHS3
YU
POWERTRAIN
CONTROL MODULE
(CONTINUED FIGURE 04.1)
-2
GU
PI35 -1
NR
-2
2/4
GY
PI34 -1
GW
-2
2/3
2/2
NW
PI33 -1
-2
GO
PI32 -1
NY
-2
2/1
GB
PI31 -1
NG
-2
1/4
GR
PI29 -1
NU
-2
1/3
GU
PI28 -1
NR
-2
GY
PI30 -1
N
-2
1/2
1/1
GY
PI25 -1
N
-2
2/4
GW
PI24 -1
NW
-2
GO
PI23 -1
NY
-2
2/3
2/2
GB
PI22 -1
NG
-2
IGNITION COILS
2/1
GR
NR
PI21 -1
1/4
GU
-2
GY
PI20 -1
N
-2
GW
NW
PI19 -1
1/3
NU
1/2
1/1
REAR
BRAKE
CANCEL
SWITCH
AIR CONDITIONING
PRESSURE SENSOR
COOLING FAN
MODULE

Jaguar V6 / V8 Engine Management #881

Transcription

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