1998 JAGUAR X308 battery

El
ectronic Engine Controls - Knock Se
nsor (KS) RH4.0L NA V8 - AJ27/3.2L
NA V8 - AJ26
Re mo
val and Installation
Remova

l
Installation

1.
Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).
2. Remove for access, appropriat e engine cover; refer to
12.30.06.

3. Disc onne
ct knock sensor conne
ctor from mounting bracket.

4. Disc
onnect connector.

5. Using speci a
l tools, crowfoot
and extension, remove knock
sensor.
1. Installation is a reversal of the removal procedure.
2. Tighten sensor to 31 - 41 Nm.

El
ectronic Engine Controls -
Mass Air Flow (MAF) Sensor
Remo
val and Installation
Remov
a
l
1.
Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).

2. Disc
onnect connector from MAF sensor.

3. Re
move bolts securing MAF sensor to air cleaner.

4. Re
move air cleaner cover.
Re
lea
se clips.

5. Re
lease band clip - trunking to MAF sensor and remove
assembly.
Di sc
ard sensor seals

El
ectronic Engine Controls - Variable
Camshaft Timing (VCT) Oil Control
Solenoid
Re mo
val and Installation
Remova

l
1.
Op
en the engine compartment and fit paintwork protection
sheets.

2. Disc
onnect the batt
ery ground cable.
Re
move the battery cover.

3. Disc
onnect the VVT solenoid connector.

4. Re
move the two bolts which secure the VVT solenoid to the
timing cover.
5. Pull the VVT solenoid clear and discard the O-ring.

I
nstallation



1.
Fi
tting a new VVT solenoid assembly is the reverse of the
removal procedure. Fit a new O-ri ng, lubricated with petroleum
jelly,.

2. F
it and tighten the two bolts to 10 - 14 Nm.
3. Remove the paintwork protection sheets and close the cover.
4. Connect the battery and fit the battery cover.
Re
fer to the Battery Reconnection Procedure 86.15.15.

Voltage is monitored at the regulators and solenoids for continuity and shorts. For example, when a solenoid is ON the
voltage on the TCM side should be ground , when OFF the voltage should be +12.
Shift Solenoid

The function of the three soleno id valves is to control the flow of transmissi on oil to the various transmission components.
Three solenoid valves are located wi thin the transmission assembly, and are closed when not energized.
Pressure Regulator

The function of the five pressu re regulators is to modulate the oil pressure to the various transmission components. The
regulators are pulse width modulated by the TCM, switching to ground potential. The other side of the regulators being
connected, via an internal TCM relay, to battery voltage. The regulator is closed when not energized by the TCM.
Transmission Fluid Temperature Sensor

2.2. Check on non-volatile diagnostic memory by wr iting a test pattern and then reading it back.
3. 3. Internal 'watchdog' hardware to check whether the TCM has crashed.
Transmission Control Module Supply Voltage
The TCM monitors battery and igni tion switched supply voltages.
A permanent supply is used to maintain a battery backed 'memor y'. Should this supply be cut, due to battery disconnection
perhaps, the 'adaptive shift' valu es will be lost. This will result in a small reduction in shift quality for a period until th e
adaptions are 're-learned'
The TCM will adopt 'limp home' mode as a result of the supply voltage being >16V or <7V with an engine speed >1600
rpm.
Should the ignition supply be >7V but <9V the TCM will hold the gear that it has currently selected. If after 2.5 seconds,
with the engine speed >1600 rpm, the voltage remains at this level, 'limp home' mode will be adopted. The 2.5 second
delay is built in to prevent reaction to a momentary voltage fluctuation.
Operation
CAUTION: Disconnection of the TCM and / or the vehicle batt ery will cause system adaptions to be lost; this may be
apparent by shift quality degradation. Fo llowing reconnection, a period of 'varied' driving will reinstate adaptions and thus
normal operation. Please ensure that the customer is made aware that the adaption period is variable and may occur after
handover, as the transmission re-learns the prevailing driving style.
• NOTE: Should the TCM fail, please ensure that the control housing cooling fan is operating correctly. Failure of the cooling
fan MUST be rectified before renewing the TCM and details of a fan fa ilure should accompany the returned TCM.
The TCM processes information received in both analogue and digital form, such as:
Transmission input speed Transmission output speed Throttle position Pedal demand Gear selector position Engine torque Engine speed Transmission oil temperature Mode switch
This information is then used by the TC M to control shift energy management and decide which shift program to implement
and which gear to select.
The TCM uses the various sensors and inpu ts to monitor the correct operation of the system an d is programmed to take
default action and inform the operator when a fault occurs.
Safety Functions
The safety functions are designed to safeguard against inappr opriate actions by the operator as well as against system
malfunctions. The system prevents reve rse gear from being engaged at high forward speeds and prevents manual
downshifting at excessive engine speeds; these functions are not operational in mechanical limp-home mode.
The TCM constantly monitors the transmissi on for faults. In the event of a problem the TCM will adopt a 'limp home' mode
in which only P R N D - (selector in D but only fourth gear is enabled) are available. The operator will be made aware of
certain faults by an in strument panel warning.
The electrical and diagnostic system has been designed such that system integrity is protected at all times, the safety
concept being based on th e following three points:

Symptom Chart
Symptom Chart
P0758
Solenoid #3 circuit fault
*GO to
P0763
*
TCM faulty
*GO to
P1605 and
P1608
*
ABS fault
CAN circuit fault between ABS/TCCM and TCM
Output speed sensor circuit fault
*
*
*GO to
P1720
*
Mechanical fault (check all other operations)
*GO to
P1726
*
Pressure regulator, solenoid
or speed sensor circuit fault
Mechanical fault - transmission defaulted to 5th?
*
*GO to
P1734
*
Pressure regulator #1 circuit fault
*GO to
P1745
*
Pressure regulator #2 circuit fault
*GO to
P1746
*
Pressure regulator #3 circuit fault
*GO to
P1747
*
Pressure regulator #4 circuit fault
*GO to
P0743
*
Pressure regulator #5 circuit fault
*GO to
P1748
*
Mechanical fault - transmission defaul
ted during 2nd to 3rd or 3rd to 4th
shift?
*GO to
P1779
*
Power (ignition) supply fault to TCM
Vehicle battery charging system fault
*
*GO to
P1789 and
P1793
*
Incompatible ECM, ABS/TCCM, TCM or INST - check part number
*GO to
P1795
*
CAN circuit fault
Check fault code(s) in ECM, ABS/TCCM or INST and rectify as required
*
*GO to
P1796
*
Faulty ECM
CAN circuit fault between ECM and TCM
*
*GO to
P1797
*
Default to 5th gearOutput speed sensor circuit fault
Mechanical fault (check pulling
away from standstill performance)
*
*GO to
P1722
*
Output / input speed sensor circuit fault
Mechanical fault (check operation of tr
ansmission in 2nd, 3rd and 4th gears)
*
*GO to
P1730
*
SymptomPossible SourcesAction
DTC P0741 Torque converter clutch system
performance or stuck offTorque converter clutch slipping or stuck off
*GO to Pinpoint
Test A
*
DTC P0742 Torque converter clutch system stuck onTorque converter clutch stuck on
*GO to Pinpoint
Test A
*
DTC P0743 Torque converter clutch system
electrical#4 pressure regulator faulty
Harness fault
Connector pins(s) bent
, loose or corroded
*
*
*GO to Pinpoint
Test B
*
DTC P0702 Transmission control system
electricalHarness fault
High side switch (FET) fault
Connector pins(s) bent
, loose or corroded
*
*
*GO to Pinpoint
Test C or D
*
DTC P0753 Shift solenoid A electricalHarness fault
Solenoid open circuit
Solenoid short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test C
*
DTC P0758 Shift solenoid B electricalHarness fault
Solenoid open circuit
Solenoid short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test C
*
DTC P0763 Shift solenoid C electricalHarness fault
Solenoid open circuit
Solenoid short
Connector pins(s) bent
, loose or corroded
*
*
*
*GO to Pinpoint
Test C
*

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
*