1994 JAGUAR XJ6 torque

Automatic Transmission (V12) ~ Pow. rtrain
Engine
Torque Reduction and Malfunction Indication
This signal, to the ECM, has three modes of operation.
1. To indicate normal engine operation to the ECM.
2. During gearshifts, to request reduction of engine torque
3. During fault conditions, to inform the ECM.
During normal operation
theTCM outputs a constant duty cycle signal to the ECM. The signal is changed when torque
reduction is required to indicate to the ECM the degree of ignition retardation necessary. If a fault condition, relating
to OBD
II CARB legislation, occurs the TCM will transmit a signal to the ECM relating this event. The ECM will only
respond to this signal if its duration is 100 milli-seconds or longer.
If the signal from the torque reduction line is either HIGH or LOW for 2 or more seconds the EMS will recognise that
a fault may be present and transmit this information to the TCM.
If the signal from the torque reduction line lasts for 2 or more seconds the EMS will return to normal operation.
Sport Mode Indicator Lamp
The sport mode indicator lamp, mounted on the instrument panel, is illuminate when sport mode is selected and the
ignition switch is ON. Sport mode is selected at a two position switch mounted to the rear of the gear selector assembly.
Gearbox Failure Warning Lamp
The gearbox failure warning lamp, mounted on the instrument panel, is illuminated when afault is detected bytheTCM within the transmission electrical or mechanical systems.
Vehicle Speed (12 cylinder vehicles only)
This output signal is calculated from the transmission output speed and supplied to the ECM as an indication of vehicle
speed.
8.2.5 DIAGNOSTIC LINKS
Diagnostic
L line
One of a two wire interface used to activate stored diagnostic codes for reading by external equipment.
Diagnostic K Line
One of a two-wire interface used to communicate stored diagnostic codes for reading by external diagnostic equip- ment.
X300 EDM 7 Issue 1 August 1994

8.2.6 DIAGNOSTIC FAULT CODES
The following codes are stored within the TCM whenever a fault is detected on the system. The codes relating to OBDll legislation can be accessed using Jaguar Diagnostic Equipment or a hand-held, proprietary scan tool.
Code 1 Description [ OBDII i Page No.
PO605 I TCM internal error Y 8 I
PO703 Brake switch input malfunction N I 9
PO706 Transmission range sensor fault Y I 10 1
1 PO7 12 Transmission fluid temperature sensor low input Y , 11
PO713 Transmission fluid temperature sensor high input Y 11
PO7 15 Turbine / input speed sensor malfunction Y 12 I
I PO716 I Turbine / input speed sensor range / performance IYll21
I PO720 I Output speed sensor circuit malfunction Iy 13 I
1 PO721 [Output speed sensor circuit range / performance Iy 13 I
I PO726 1 Engine speed input circuit performance Iy 14 I PO727 Engine speed input circuit no signal Y I 14
PO730 Incorrect gear ratio Y 15
PO7 4 1 TCC system stuck off Y 16
PO742 TCC system stuck on Y 16
16
PO743 TCC system electrical
17 Pressure control solenoid electrical PO748
ZhTfi solenoid A performance Y 18 PO751
__ p0753-- - -- Shift solenoid A electrical Y 18
Shift solenoid B performance Y I 18 PO756
PO758 Shift solenoid B electrical Y 18
PO780 Shift malfunction (Max-adapt) N 19
PI739 Transmission component slipping Y 19
- __ -
___ __ Y
N - ~_ ~
~
- _____ - __.__ ~ ~~~
~~
I
___. ________ I
__
PI780 Torque
reduction signal malfunction Y 20
PI781 Engine torque signal malfunction Y 20
PI782 Traction active input fault N 22
PI783 Transmission over temperature condition N - I I PI791 I Throttle position electrical signal failure Y 23
Issue 1 August 1994 8 X300 EDM

Srake Switch lnpiit Malfiincfion - PO703
Function:
Monitoring of brake switch operation.
Connection: TCM Connector
CC048/025 CC003/009
Possible causes:
. Faulty switch, wiring or connection.
Effects:
Torque converter clutch operation may be abnormal.
Remedy:
. Repair or renew switch, wiring or connector. Switch
CA072/001
Ground
CA002/002
P2!
1
Brake
switch input malfunction -fault code PO703
I -I I I I I I ,I
J86 - 1741 Fig. 1
Issue 1 August 1994 10 X300 EDM

Automatic Transmission (V12) Powertrain
Input Speed Sensor - range /performance and malfunction - PO715 / PO716
Function:
Received speed monitoring.
Transmission Connector
(GB014)
PIN 02
PIN 01
Connections: TCM Multi-pl ug
Connector
(CC048) (GB015)
PIN 37 PIN 03
PIN 50 PIN 04
Data:
Sensor resistance = 1.25kQ f 0.25
Possible causes:
9 Faulty sensor.
9 Faulty harness wiring 1 connectors.
Effects:
. MIL illuminated.
. Harsh gearshifts, no torque converter clutch control.
. No fourth drive gear (Fault Code PO716 only).
Remedy:
. Repair or renew harness 1 connectors.
Renew sensor.
0
0
1
Input speed sensor - fault code PO715 / PO716
J86 - 1714
Fig. 1
X300 EDM 13 Issue 1 August 1994

Powertrain Automatic Transmission (V12)
TCC Stuck Off / On or Malfunction - PO74 1 / PO742 / PO743
Function:
Torque converter clutch operation monitoring.
Connections: TCM Multi-plug Connector
CCO48/042 GBOlO/OO1
GB010/003 (12V)
Possible causes:
. Faulty harness wiring 1 connection.
. Faulty torque converter clutch solenoid.
. Mechanical failure, eg slippage.
Effects:
. MIL illuminated.
' No TCC control (Not Fault Code P0742).
Harsh gearshifts or stalling (Fault Code PO742 only).
Remedy:
. Repair or renew harness 1 connectors.
Refer to VSM, Section 8.2.
. Renew TCC solenoid. TCC
Connector
GBOl2/009
GBO 1210 10
PQ:
1 Torque con
Fig. 1
01 clutch -fault codes PO741 1 PO743 I PO748
J80 - IT47
Note: * +12V present only when ignition switched ON
X300 EDM 17 Issue 1 August 1994

Automatic Transmission (V12) Powertrain
Shift Malfunction (Max- Adapt) - PO780
Function:
Transmission internal operation monitoring.
Possible causes:
. Mechanical wear 1 failure.
Effects:
. Harsher shifts.
Remedy:
. Refer to VSM, Section 8.2.
Transmission Component Slipping - PI 739
Function:
Transmission internal operation monitoring.
Possible causes:
Faulty harness wiring /connection.
. Fuse blown.
. Faulty torque converter clutch.
Mechanical wear.
Effects:
. MIL lamp illuminated.
. Harsh shifts.
Remedy:
. Repair or renew harness 1 connector.
Renew fuse F14 in LH heelboard fuse-box on determining reason for rupture.
Refer to VSM, Section 8.2.
0
0
Issue 1 August 1994 20 X300 EDM

Automatic Transmission (V12) Powertrain
Torque Reduction Signal Malfunction - P1780
Function:
ECM signal monitor.
Connections: TCM PI Harness ECM
CC048/007 P1063/008 P1044/006
Possible causes:
. Faulty harness wiring /connection.
. Faulty ECM signal.
Effects:
. Harsh gearshifts.
Remedy:
. Repair or renew harness / connector.
Examine ECM fault diagnosis (refer to EDM, section 5.2).
Transmission
warning lamp illuminated.
Engine Torque Signal Malfunction - P1781
Function:
ECM signal monitor.
Connections: TCM PI Harness
CC048/0 12 P1063/007
ECM
P1044/005
Possible causes:
. Faulty harness wiring /connection.
. Faulty ECM signal.
Effects:
. Transmission warning lamp illuminated.
. Harsh gearshifts.
Remedy:
Repair or renew harness / connector.
Examine ECM fault diagnosis (refer
to EDM, section 5.2).
X300 EDM 21 Issue 1 August 1994

Automatic Transmission (V12) W Powertrain
1
Torque reduction / engine torque signal malfunction - PI780 / PI781
-
8
J86.175~3
Fig. 1
Note: * Torque reduction request * Torque reduction signal
0
0
0