engine JAGUAR X308 1998 2.G Workshop Manual

1.1. The hydraulic system has 'fail-safe' characteristics regardin g its electrical operation, such that should the power
supply be lost to the electro-hydraulic actuators the transmission will initiate a limp-home mode.
2. 2. Recognition of critical shift operation by monitoring the last element in the signal path, ie the solenoid valve, and
checking by means of redundant me asured variables, ie engine speed, input speed and output speed.
3. 3. Each time the vehicle is started there is a check on the entire safety hardware and the associated program parts
and signal paths. A malfunction in this part of the system, or triggering of the safety circuit, is communicated to
the operator through the illumination of the transmission warning lamp.
TCM Inputs
Input Speed Sensor (Torque Converter Turbine)
The input speed sensor provides the TCM with transmission inpu t shaft speed information. This signal is produced from an
inductive pick-up, generating 30 pulses per revolution.
Transmission Output Speed Sensor
The output speed sensor provides the TCM with transmission ou tput shaft speed information. This signal is produced from
an inductive pick-up, generati ng 36 pulses per revolution.
Transmission Oil Temperature Sensor
A thermistor which provides an electrical indication of the oi l temperature to the TCM. The signal is measured as a voltage
with reference to analog ue ground in the TCM.
Kickdown Switch (where fitted)
Kickdown is intended to provide maximum vehicle acceleration , via the appropriate downshift(s), when the operator uses
full throttle. A kickdown switch provides an electrical signal to the TCM wh en the accelerator pedal is fully pressed. The
switch is normally open, connected to vehicle ground. Should the switch fail the TCM will detect kickdown using the
accelerator pedal position.
Throttle Pedal Stop (where fitted)
This component, used where the kickdown switch is not fitted, limits throttle pedal travel .in the same way. The kickdown
feature is retained, but is controlled by throttle position only. The pedal stop must be set, using the PDU, in the same way
as the kickdown switch to optimize performance.
Mode Selection Switch
The mode selection switch is a two position switch indicati ng to the TCM the current performance mode selected by the
driver. The switch generates a tw o-bit digital input to the TCM.
Rotary Position Switch
The rotary position switch detects the position of the transmis sion selector shaft. The switch is supplied as part of a new
transmission assembly, mounted on the transmission body. The swit ch is used to indicate to the TCM the six positions of the shaft: Park, Reverse, Neutral, Drive, Third and Second. The switch provides a four-bit input to the TCM.
Drive to Fourth Switch
Detects the movement of the selector lever from Drive to Fourth position. The selector cable, and therefore the transmission selector shaft, does not move as the lever is operated between these two positions. The switch is located within the 'J-gate'
assembly, producing a digital output to indicate to the TCM that the lever has moved from D to 4 .
Serial Communications Interfaces

Controller Area Network (CAN)
The TCM is an integral part of the CAN system which facilitates the interchange of real-time data between control modules
and sensors. Please see section 303- 14 for a full description of CAN.
OBDII Interface
Data concerning OBDII related transmission failures is stored in the ECM for access via the J1962 socket.
System Functions
Range Selection
The selector lever is connected to the transmission via a bowden cable, which operates the transmission selector shaft
between all positions except Drive to 4 .
The TCM detects the gear selected by means of a rotary position switch fitted to the transmission selector shaft. A separate
Drive to 4 switch is located within the 'J' gate' assembly.
Movement of the selector lever between Park, Reverse, Neutral and Drive manually directs th e flow of transmission oil; the
TCM having control of the forward gears selected while the lever is in the Drive position.
Shift Point Selection
The gearshift points are selected, by the TCM, as a function of the output speed, engine load, selector position and shift
program selected. The operator has control over the shift points via the selector lever, throttle pedal movement, kickdown
function and mode switch.
'J' Gate Layout

Mode Switch
This switch allows the driver to select one of two base shift maps; Normal and Sport modes, the switch being illuminated
when Sport is selected.
Special Shift Programs
These specific condition shift maps are available to enhance the operation of the vehicle under specific driving conditions.
and are listed below in order of priority / title and operating condition.
1. 1. Traction: When traction intervention is active
2. 2. Hot mode: Extreme engine / transmission temperatures

3.3. Gradient: Under specific speeds and loads
4. 4. Cruise: During cruise control
5. 5. Manual: Shift map when the LH side of the 'J gate' is used
Three specific condition shift maps have a higher priority than the two base shift maps and will intervene when appropriate
conditions prevail for traction, gradient or cruise.
When traction control (engine or brake system derived) is operational the TCM will implement the traction map to maximise
control of wheel slip.
The gradient maps are intended to enhance vehicle drivability when towing or climbing a gradient. The TCM will implement
the maps when increased driving resistan ce is detected and enhanced drivability, cooling and increa sed performance is
appropriate.
The cruise map is intended to minimize unwanted gearshifts and 'hunting' and is activated when cruising near to the set
speed, or resuming.
Connector Pins Identification
Connector Pin Identity Chart for EM007

Pin NumberCircuit Function
001Pressure regulator 2
002Mode switch status
003Not used
004Pressure regulator #4
005Pressure regulator #1
006Power ground
007Not used
008Rotary switch L2
009Rotary switch L4
010 to 011Not used
012Mode switch Pin B (Sport)
013D to 4 switch
014Input speed sensor (-)
015Output speed sensor (screen)
016Output speed sensor (+)
017Not used
018Kickdown switch (where used)
019 to 020Not used
021Analogue ground
022Fluid temperature sensor
023Input speed sensor (screen)
024 to 025Not used
026B+
027Not used
028Digital ground
029Pressure regulator #3

Automatic Transmission/Transaxle - 4.0L NA V8 - AJ27/3.2L NA V8 - AJ26
- Diagnostic Strategy
Diagnosis and Testing
Quick Reference Fault Chart
Quick Reference Fault Chart
Special Tool(s)

Digital multimeter

Generic scantool
SymptomPossible SourcesAction
Normal transmission
operation but fault codes
stored• NOTE: If P0706 is logged ignore P0742
Output speed sensor circuit fault
TCM faulty
ABS system fault (this code may log er roneously following an ABS problem)
Position switch and D to 4 switch circuit fault
P R 4 circuit fault

*
*
*
*
*
GO to
P0721 GO to
P1603 GO to
P0742
*
*
*
Sport mode will not selectMode switch circuit fault
*GO to
P0790
*
Mode switch state lamp not
workingMode switch supply
Mode switch circuit fault
*
*GO to
P0790
*
Poor, or reduced shift
qualityPresence of EMS faults
(may affect the accuracy of the torque signal)
*GO to EMS *
Transmission temperature sensor circuit
*GO to
P0710
*
Out of sequence shiftOutput / input speed sensor circuit fault
Mechanical fault (check all other operations)
*
*GO to
P1731
*
No torque converter lock-
upP R 4 circuit fault
*GO to
P0743
*
Mechanical fault, should P R 4 be OK
*GO to
P0741
*
Harsh shifts, engine stalling (torque converter stuck on)P R 4 circuit fault
Mechanical fault, should P R 4 be OK
*
*GO to
P0742
*
Default to 4th gearSolenoid / pressure regulator supply from TCM
*GO to
P0702
*
• NOTE: If the code logs wh
en 3rd is selected, then the D to 4 switch is the most probable cause If the code logs when D is selected fro m the LH side of the gate,
then check selector cable adjustment
'J gate' or selector ca ble out of adjustment
D to 4th switch
Rotary position switch circuit
*
*
*GO to
P0706
*
Input speed sensor circuit fault
Input speed sensor faulty
*
*GO to
P0715
*
Solenoid #1 circuit fault
*GO to
P0753
*
Solenoid #2 circuit fault
*GO to
*

DTC P1745 Pressure regulator 1 malfunctionHarness fault
Pressure regulator open circuit
Pressure regulator short
Connector pins(s) bent, loose or corroded
*
*
*
*GO to Pinpoint
Test D
*
DTC P1746 Pressure regulator 2 malfunctionHarness fault
Pressure regulator open circuit
Pressure regulator short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test D
*
DTC P1747 Pressure regulator 3 malfunctionHarness fault
Pressure regulator open circuit
Pressure regulator short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test D
*
DTC P0743 Torque converter clutch system
electricalHarness fault
Pressure regulator open circuit
Pressure regulator short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test D
*
DTC P1748 Pressure regulator 5 malfunctionHarness fault
Pressure regulator open circuit
Pressure regulator short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test D
*
DTC P0721 Output / turbine speed sensor circuit
malfunction• NOTE: This DTC is non OBDII but is included for
reference to P1720
Output speed sensor signal faulty
Harness fault
Connector pins(s) bent , loose or corroded
Damaged harness screen
*
*
*
*GO to Pinpoint
Test E
*
DTC P1720 Loss of output speed and wheel
speed informationAs P0721
ABS fault
*
*GO to Pinpoint
Test E
*
DTC P0715 Input / turbine speed sensor circuit
malfunctionInput speed sensor signal faulty
Harness fault
Connector pins(s) bent
, loose or corroded
Damaged harness screen
*
*
*
*GO to Pinpoint
Test F
*
DTC P1722 Stall speedOutput speed sensor signal faulty
Harness fault
Connector pins(s) bent
, loose or corroded
TCM failure
Transmission mechanical fault
*
*
*
*
*GO to Pinpoint
Test G
*
DTC P1726 Engine overspeed malfunctionTransmission mechanical fault
*GO to Pinpoint
Test H
*
DTC P1730 Gear control malfunction 2,3,5,Input speed sensor signal faulty
Output speed sensor signal faulty
Harness fault
Connector pins(s) bent
, loose or corroded
TCM failure
Transmission mechanical fault
*
*
*
*
*
*GO to Pinpoint
Test I
*
DTC P1734 Gear control malfunction 4Input speed sensor signal faulty
Output speed sensor signal faulty
Harness fault
Connector pins(s) bent
, loose or corroded
TCM failure
Transmission mechanical fault
*
*
*
*
*
*GO to Pinpoint
Test I
*
DTC P1779 Load control malfunctionInput speed sensor signal faulty
Output speed sensor signal faulty
Harness fault
Connector pins(s) bent
, loose or corroded
TCM failure
Transmission mechanical fault
*
*
*
*
*
*GO to Pinpoint
Test I
*
DTC P1603 EEPROM malfunctionSee Monitoring Procedure
*GO to Pinpoint
Test J
*
DTC P1605 TCM checksum failureSee Monitoring Procedure
*GO to Pinpoint
Test J
*
DTC P1608 Watchdog malfunctionSee Monitoring Procedure
*GO to Pinpoint
Test J
*
DTC P1793 Ignition supply malfunction >16 < 7
voltsBattery charging system fault
Harness fault
Connector loose or corroded
*
*
*GO to Pinpoint
Test K
*

Pinpoint test A: P0741, P0742, P0743
Pinpoint test B: P0743
Connector pin(s) bent or tracking between
connections
*
DTC P1789 Ignition supply malfunction >7 < 9
voltsBattery charging system fault
Blown fuse
Harness fault
Connector loose or corroded
Connector pin(s) bent or tracking between
connections Ground fault
*
*
*
*
*
*GO to Pinpoint
Test K
*
DTC P0710 Transmission fluid temperature
sensor malfunctionDamaged sensor
Sensor out of range / short
Harness open circuit
Harness short
Connector loose or corroded
*
*
*
*
*GO to Pinpoint
Test L
*
PINPOINT TEST A : P0741, P0742, P0743
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
A1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to A2
A2: RENEW TORQUE CONVERTER
Renew the torque converter 1
Has the torque converter been renewed?
Yes GO to A3
A3: END
Drive the vehicle for a period from cold to include idle, brisk
acceleration and steady state cruising up to and including
normal engine temperature. Check for the presence of DTC. 1
Has the fault code cleared?
Yes STOP
No Contact Jaguar Service
PINPOINT TEST B : P0743
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
B1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present

Pinpoint test D: P0702, P1745, P1746, P1747, P0743, P1748
Renew the solenoid; refer to 44.15.50.
C13: INTERNAL TRANSMISSION HARNESS CHECK
Measure the resistance from transmission internal harness
multiplug to the relevant solenoid connector 1
Is the resistance < 0.5 OHM?
Yes GO to C14
No Renew the internal harnes s; refer to 44.15.35.
C14: END
Cycle the ignition ON - (OFF for 2 minutes) - ON, start the
engine and run >1600 rpm 1
Has the fault code cleared?
Yes
STOP
No P0702 present?
Yes GO to D1
No P0753, P0758, P0763 present?
Yes Contact Jaguar Service
PINPOINT TEST D : P0702, P1745, P1746, P1747, P0743, P1748
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
D1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to D2
D2: CHECK HARNESS +VE CONTINUITY

Pinpoint test E: P1720 (P0721)
GO to D13
No Renew the pressure regulator; refer to 44.15.51.
D13: INTERNAL TRANSMISSION HARNESS CHECK
Measure the resistance from transmission internal harness
multiplug to the relevant pr essure regulator connector 1
Is the resistance < 0.5 OHM?
Yes
GO to D14
No Renew the internal harnes s; refer to 44.15.35.
D14: END
Cycle the ignition ON - (OFF for 2 minutes) - ON, start the
engine and run >1600 rpm 1
Has the fault code cleared?
Yes
STOP
No Contact Jaguar Service
PINPOINT TEST E : P1720 (P0721)
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
E1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present.
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to E2
E2: CHECK HARNESS +VE CONTIN UITY (OUTPUT SPEED SENSOR)

Pinpoint test H: P1726
Pinpoint test I: P1730, P1734, P1779
G8: END
Perform appropriate service drive cycle and check for the
presence of DTC. 1
Has the fault code cleared?
Yes STOP
No Contact Jaguar Service
PINPOINT TEST H : P1726
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
H1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present.
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to H2
H2: RENEW TRANSMISSION
Renew the transmission 1
Has the transmission been renewed?
Yes GO to H3
H3: END
Drive the vehicle for a period from cold to include idle, brisk
acceleration and steady state cruising up to and including
normal engine temperature. Check for the presence of DTC 1
Has the fault code cleared?
Yes STOP
No Contact Jaguar Service
PINPOINT TEST I : P1730, P1734, P1779
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
I1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present.

Pinpoint test K: P1789, P1793
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to J2
J2: RENEW TCM
Renew the TCM 1
Has the TCM been renewed?
Yes GO to J3
J3: END
Drive the vehicle for a period from cold to include idle, brisk
acceleration and steady state cruising up to and including
normal engine temperature. Check for the presence of DTC 1
Has the fault code cleared?
Yes STOP
No Contact Jaguar Service
PINPOINT TEST K : P1789, P1793
TEST CONDITIONSDETAILS/RESULTS/ACTIONS
K1: RETRIEVE DTCS
• NOTE: Battery and or ECM disconnection prior to scanning wi ll erase all data, ensure that the correct DTC is present.
Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to K2
K2: CHECK FUSE