Ground JAGUAR X308 1998 2.G Workshop Manual

Electron
ic Engine Controls -
Heated Oxygen Sensor (HO2S) LH
Rem
oval and Installation
General Equipment
Remov
al
Installation


Snap
-on tool S6176
1. WARNING: ENSURE THAT TH E EXHAUST AND CATALYST
ARE COLD BEFORE COMMENCING WORK
Disconnect the battery ground lead.

2.

CAUTION: Make sure the wiring harness is not twisted or
damaged on removal. Failure to follow this instruction may result in
damage to the vehicle.
From inside the engine compartm ent, release the relevant sensor
(s) multiplug from its mounting bracket and disconnect the plug.
3.

To gain access to the sensor(s) the front muffler assembly must
be displaced for clearance; refer to 30.10.18.

4.

CAUTION: Make sure the wiring harness is not twisted or
damaged on removal. Failure to follow this instruction may result in
damage to the vehicle.
• NOTE: Right-hand shown, left-hand similar.
Using the Snap-on tool S6176, remove the sensor.
1.

Fitting is the reverse of the remo val procedure, noting that a new
sealing washer should be used.

2.

CAUTION: Make sure the wiring harness is not twisted or
damaged on installation. Failure to follow this instruction may result
in damage to the vehicle.
• NOTE: Right-hand shown, left-hand similar.
Tighten the sensor to specification.
3.

Make good the exhaust seals.

Electronic
Engine Controls -
Heated Oxygen Sensor (HO2S) RH
Remo
val and Installation
General Equipment
Remov a
l
Installation


Snap -on to
ol S6176
1. WARNING: ENSURE THAT TH E EXHAUST AND CATALYST
ARE COLD BEFORE COMMENCING WORK
Disconnect the battery ground lead.

2. CAU
TION: Make sure the wiring harness is not twisted or
damaged on removal. Failure to follow this instruction may result in
damage to the vehicle.
• NOTE: Left-hand shown, right-hand similar.
From inside the engine compartm ent, release the relevant sensor
(s) multiplug from its mounting bracket and disconnect the plug.
3. To
gain access to the sensor(s)
the front muffler assembly must
be displaced for clearance; refer to 30.10.18.

4. CAU
TION: Make sure the wiring harness is not twisted or
damaged on removal. Failure to follow this instruction may result in
damage to the vehicle.
Using the Snap-on tool S6176, remove the sensor.
1. Fittin
g is the reverse of the remo
val procedure, noting that a new
sealing washer should be used.

2. CAU
TION: Make sure the wiring harness is not twisted or
damaged on installation. Failure to follow this instruction may result
in damage to the vehicle.
Tighten the sensor to specification.
3. M
ake good the exhaust seals.

El
ectronic Engine Controls - Knock Se
nsor (KS) LH4.0L 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. NO TE
: Bank 1 shown.
Disconnect knock sensor conne ctor from mounting bracket.

4. Disc
onnect connector.

5. NO TE
: Bank 1 shown.
Using special 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 - 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.

Op
eration
The T
ransmission Control Module (TCM) is
able to monitor the state of the torque converter clut ch at all times.
There are three operating modes for the converter
1. 1. Fully open - Torque converter 'unlocked'
2. 2. Fully closed - Torque converter 'locked'
3. 3. Slip control - The TCM monitors slip and may apply sufficie nt pressure to allow a small degree of slip. This mode
maximises economy by reducing slip to a minimum whilst providing isolation from drive-line shunt and vibration.
The TCM constantly measures the slip within the torque conver ter by comparing engine speed (via CAN) and input (turbine
speed). Differences in these speeds indicate the amount of slip.
Clutch Hydraulic Pressure Regulation
The T
CM supplies an internally switched +1
2V supply to the #4 pressure regulator. The regulator is operated by switching
the other side of the operating winding to ground. Hydraulic pressure is controlled by 'pulse width modulation' (PWM) of the
ground switching signal i.e. the duty cycle; the time that the pressure regulator is switched on.
Hydraulic Control
- Transmission Pre
ssure Regulators an d Shift Solenoids

Opera
tion
F
l
uid flow within the transmission assembly is controlled
by three solenoid valves and five pressure regulators.
The TCM supplies an internally switched +12V supply to each sh ift solenoid and pressure regulator. Hydraulic pressure from
the pressure regulators is controlled by 'pulse width modulation' (PWM) of the ground switching signal i.e. the duty cycle;
the time that the pressure regu lator is switched on. Control of the solenoids is effected by switching one side to ground
through the TCM.
During normal operation the TCM monitors 'Switch On' of the so lenoids, regulators and the TCM output stages, but does not
check output stage 'Switch Off'.
It e
m
Par
t
Number
De
scr
iption
1—Shif
t Sole
noid #3
2—Shif
t Sole
noid #2
3—Shif
t Sole
noid #1
4—Pressure R
e
gulator #5
5—Pressure R
e
gulator #4
6—Pressure R
e
gulator #3
7—Pressure R
e
gulator #2
8—Pressure R
e
gulator #1

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

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