automatic transmission JAGUAR XJ6 1997 2.G User Guide

Lubricants and fluids
Refer to “Weekly checks”
Capacities
Engine oil
Including oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0 litres
Cooling system
All models (approximate):
From dry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.8 litres
Drain and refill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 litres
Transmission
Automatic transmission (approximate):
From dry:
3.2 litre model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4 litres
3.6 and 4.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0 litres
Drain and refill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litres
Differential
All models (approximate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 litres
Cooling system
Antifreeze mixture:
50% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection down to -37°C (5°F)
55% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection down to -45°C (-22°F)
Note:Refer to antifreeze manufacturer for latest recommendations.
Ignition system
Spark plugs:
Type:
3.2 litre model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RC12YCC
3.6 and 4.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RC9YCC
Electrode gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9 mm
*The spark plug gap quoted is that recommended by Champion
for their specified plug listed above. If spark plugs of any other type
are to be fitted, refer to their manufacturer’s recommendations.
Engine firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5-3-6-2-4
Distributor rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clockwise
Ignition timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 5
Brakes
Disc brake pad friction material minimum thickness:
Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 mm
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 mm
Handbrake shoe friction material minimum thickness . . . . . . . . . . . . . . 1.5 mm
Handbrake adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 to 5 clicks
Torque wrench settingsNm lbf ft
Automatic transmission sump pan bolts . . . . . . . . . . . . . . . . . . . . . . . . 8 6
Automatic transmission dipstick tube nut . . . . . . . . . . . . . . . . . . . . . . . 20 15
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 28 17 to 21
Wheel nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 75
1•2Servicing specifications
3261 Jaguar XJ6
Cylinder location and distributor rotation

The maintenance intervals in this manual are provided with the
assumption that you, not the dealer, will be carrying out the work.
These are the minimum maintenance intervals recommended by us for
vehicles driven daily. If you wish to keep your vehicle in peak condition
at all times, you may wish to perform some of these procedures moreoften. We encourage frequent maintenance, because it enhances the
efficiency, performance and resale value of your vehicle.
When the vehicle is new, it should be serviced by a factory-
authorised dealer service department, in order to preserve the factory
warranty.
Maintenance schedule 1•3
1
3261 Jaguar XJ6
Weekly, or every 250 miles (400 km)
m mCarry out all the operations given in “Weekly
checks”at the start of this manual.
m
mRenew the fuel filter (Section 18)
m mCheck the ignition system components (Section 19)
m mCheck the crankcase ventilation system
(Section 20)
m mCheck the condition and tension of the drivebelt(s)
(Section 21)
m mCheck the front wheel bearing adjustment and
repack with grease (Section 22)
m mCheck the propshaft fasteners are tightened to the
specified torque (Section 23)
m mCheck the front wheel alignment (Section 24)
m mCheck the headlight beam alignment (Section 25)
Every 7500 miles (12 000 km)
or 6 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the engine oil and filter (Section 3)
m mCheck the spark plugs (Section 4)
m mCheck the power hydraulics fluid level (Section 5)
m mCheck the battery (Section 6)
m mCheck all pipes and hoses for signs of damage or
leakage (Section 7)
m mCheck the automatic transmission fluid level
(Section 8)
m mCheck the differential oil level (Section 9)
m mCheck the condition of the exhaust system
(Section 10)
m mCheck the brake pads and discs for wear and
adjust the handbrake (Section 11)
m mCheck the steering and suspension components
for wear or damage and check the wheel nuts are
tightened to the correct torque (Section 12)
m mCheck the condition of the seat belts (Section 13)
m mLubricate all locks and hinges, and exposed cables
(Section 14)
m mCarry out a road test (Section 15)
Every 2 years, regardless of mileage
m
mRenew the coolant (Section 30)
Every 60 000 miles (96 000 km)
In addition to the operations listed previously, carry out the following:
m
mCheck the handbrake shoes for wear (Section 29)
Every 30 000 miles (48 000 km)
or 2 years, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the automatic transmission fluid and filter
(Section 26)
m mRenew the differential oil (Section 27)
m mRenew the brake fluid (Section 28)
Every 15 000 miles (24 000 km)
or 12 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the spark plugs (Section 16)
m mRenew the air cleaner element (Section 17)

1•4Maintenance - component location
3261 Jaguar XJ6
1 Battery
2 Oil filler cap
3 Engine oil dipstick (not visible)
4 Automatic transmission
dipstick (not visible)
5 Brake fluid reservoir
6 Coolant reservoir
(expansion tank)
7 Air cleaner housing
8 Upper radiator hose
9 Spark plugs
10 Distributor
11 Windscreen washer fluid
reservoir
12 Power hydraulic system fluid
reservoir
13 Power steering fluid reservoir
Underbonnet view from the left-hand side of the vehicle Underbonnet view from the right-hand side of the vehicle
1 Battery
2 Oil filler cap
3 Engine oil dipstick (not visible)
4 Automatic transmission
dipstick (not visible)
5 Brake fluid reservoir
6 Coolant reservoir (expansion
tank)
7 Air cleaner housing
8 Upper radiator hose
9 Spark plugs
10 Distributor
11 Windscreen washer fluid
reservoir
12 Power hydraulic system fluid
reservoir
13 Power steering fluid reservoir

leak be found, renew the offending gasket or
oil seal by referring to the appropriate
Chapters in this manual.
2Also check the security and condition of all
the engine-related pipes and hoses. Ensure
that all cable ties or securing clips are in place
and in good condition. Clips which are broken
or missing can lead to chafing of the hoses,
pipes or wiring, which could cause more
serious problems in the future.
3Carefully check the radiator hoses and
heater hoses along their entire length. Renew
any hose which is cracked, swollen or
deteriorated. Cracks will show up better if
the hose is squeezed. Pay close attention
to the hose clips that secure the hoses to the
cooling system components. Hose clips can
pinch and puncture hoses, resulting in cooling
system leaks.
4Inspect all the cooling system components
(hoses, joint faces etc.) for leaks. A leak in the
cooling system will usually show up as white-
or rust-coloured deposits on the area
adjoining the leak. Where any problems of this
nature are found on system components,
renew the component or gasket with
reference to Chapter 3.
5From within the engine compartment,
check the security of all fuel hose attachments
and pipe unions, and inspect the fuel hoses
and vacuum hoses for kinks, chafing and
deterioration.
6Also check the condition of the power
steering fluid hoses and pipes.
8 Automatic transmission
fluid level check
1
1The level of the automatic transmission fluid
should be carefully maintained. Low fluid level
can lead to slipping or loss of drive, while
overfilling can cause foaming, loss of fluid and
transmission damage.
2The transmission fluid level should only be
checked when the transmission is at its
normal operating temperature.
Caution: If the vehicle has just been driven
for a long time at high speed or in city
traffic in hot weather, or if it has been
pulling a trailer, an accurate fluid level
reading cannot be obtained. Allow the fluid
to cool down for about 30 minutes.
3If the vehicle has not been driven, park the
vehicle on level ground, set the handbrake,
then start the engine and bring it to operating
temperature. While the engine is idling,
depress the brake pedal and move the
selector lever through all the gear ranges,
beginning and ending in Park.
4With the engine still idling, remove the
dipstick from its tube (see illustration). Check
the level of the fluid on the dipstick (see
illustration)and note its condition.
5Wipe the fluid from the dipstick with a clean
rag and reinsert it back into the filler tube until
the cap seats.6Pull the dipstick out again and note the fluid
level. If the transmission is cold, the level
should be in the COLD or COOL range on the
dipstick. If it is hot, the fluid level should be in
the HOT range. If the level is at the low side of
either range, add the specified transmission
fluid through the dipstick tube with a funnel.
7Add just enough of the recommended fluid
to fill the transmission to the proper level. It
takes about one pint to raise the level from the
low mark to the high mark when the fluid is
hot, so add the fluid a little at a time and keep
checking the level until it is correct.
8The condition of the fluid should also be
checked along with the level. If the fluid at the
end of the dipstick is black or a dark reddish
brown colour, or if it emits a burned smell, the
fluid should be changed (see Section 26). If
you are in doubt about the condition of the
fluid, purchase some new fluid and compare
the two for colour and smell.9 Differential oil level check
1
1The differential has a check/fill plug which
must be removed to check the lubricant level.
If the vehicle is raised to gain access to the
plug, be sure to support it safely on axle
stands - DO NOT crawl under the vehicle
when it’s supported only by the jack!2Remove the lubricant check/fill plug from
the differential (see illustration).Use a
3/8-inch drive ratchet and a short extension to
unscrew the plug.
3Use your little finger as a dipstick to make
sure the lubricant level is even with the
bottom of the plug hole. If not, use a syringe
or squeeze bottle to add the recommended
lubricant until it just starts to run out of the
opening.
4Refit the plug and tighten it securely.
10 Exhaust system check
1
1With the engine cold (at least three hours
after the vehicle has been driven), check the
complete exhaust system from its starting
point at the engine to the end of the tailpipe.
This should be done on a hoist where
unrestricted access is available.
2Check the pipes and connections for
evidence of leaks, severe corrosion or
damage. Make sure that all brackets and
hangers are in good condition and tight (see
illustration).
3At the same time, inspect the underside of
the body for holes, corrosion, open seams,
etc. which may allow exhaust gases to enter
the passenger compartment. Seal all body
openings with silicone or body putty.
4Rattles and other noises can often be
traced to the exhaust system, especially the
mounts and hangers. Try to move the pipes,
Every 7500 miles or 6 months 1•11
1
9.2 The differential check/fill plug is
located on the rear of the differential
housing - place your finger in the filler plug
hole to make sure the lubricant level is
even with the bottom of the hole
10.2 Check the exhaust system hangers
(arrowed) for damage and cracks
3261 Jaguar XJ6
8.4a The automatic transmission dipstick
(arrowed) is located in a tube which
extends forward from the transmission
8.4b Check the automatic transmission
fluid with the engine idling at operating
temperature and the gear selector in Park,
then add fluid to bring the level to the
upper mark

26 Automatic transmission fluid
and filter renewal
2
1At the specified time intervals, the
transmission fluid should be drained and
renewed. Since the fluid will remain hot long
after driving, perform this procedure only after
the engine has cooled down completely.
2Before beginning work, purchase the
specified transmission fluid and a new filter.
3Other tools necessary for this job include
axle stands to support the vehicle in a raised
position, a drain pan capable of holding at
least eight pints, newspapers and clean rags.4Raise the vehicle and support it securely on
axle stands.
5Place the drain pan under the drain plug in
the bottom of the transmission sump pan.
Remove the plug and allow the fluid to drain
(see illustration).
6Refit the drain plug, then move the drain
pan underneath the dipstick tube. Loosen the
dipstick tube collar and let the remaining fluid
drain (see illustrations).
7Remove the sump pan mounting bolts and
brackets (see illustration).
8Detach the sump pan from the transmission
and lower it, keeping it as horizontal as
possible in order not to spill too much of the
remaining fluid (see illustration).9Drain the remaining fluid from the
transmission sump pan, clean it with solvent
and dry it with compressed air. Be sure to
clean the metal filings from the magnet, if
equipped.
10Remove the screws and detach the filter
from the valve body (see illustrations).
11Refit the new O-ring and filter, being sure
to tighten the bolts securely.
12Carefully clean the fluid pan-to-
transmission sealing surface.
13Make sure the gasket surface on the
transmission sump pan is completely clean,
then refit the gasket. Put the sump pan in
place against the transmission and refit the
brackets and bolts. working around the sump
pan, tighten each bolt a little at a time until the
torque listed in this Chapter’s Specifications
is reached. Don’t overtighten the bolts!
Connect the dipstick tube and tighten the
collar securely.
14Lower the vehicle and add the specified
amount of fluid through the filler tube (see
Section 8).
15With the transmission in Park and the
handbrake set, run the engine at fast idle, but
don’t race it.
16Move the gear selector through each
position, and then back to Park. Check the
fluid level.
17Be sure to check underneath the car for
any leaks after the first few miles of driving.
Every 30 000 miles (48 000 km) or 2 years
Every 30 000 miles or 2 years 1•19
1
26.6a Unscrew the dipstick tube collar26.6b Detach the tube and let the
remaining fluid drain
26.7 Use a socket and extension to
remove the transmission sump pan bolts
and brackets26.8 Lower the sump pan from the
transmission
26.10a Use a Torx-head driver to remove
the filter bolts (arrowed) . . .
3261 Jaguar XJ6
26.5 Using an Allen spanner remove the
drain plug located in the bottom of the
transmission sump pan
26.10b . . . then remove the fluid filter from
the transmission26.10c Be sure to remove the old O-ring
from the transmission - always use a new
O-ring when replacing the filter

5If equipped with an automatic transmission,
disconnect the cooler lines from the radiator
(see illustrations). Disconnect the cooling fan
switch connector (see illustration 4.15).
Place a drip pan to catch the fluid and cap the
fittings. Note:The transmission oil cooler lines
enter the radiator on the left, while the power
steering cooler lines attach on the right side of
the radiator. On 1993 and 1994 models, the
cooler fittings require a spring-lock coupling
tool, normally used on fuel lines or air
conditioning lines.
6Remove the four bolts from the radiator
cowl panel and take off the panel (see
illustration).
7Lift out the radiator. Be aware of dripping
fluids and the sharp fins. Take care not to
damage the radiator fins by contact with other
parts.
8With the radiator removed, it can be
inspected for leaks, damage and internal
blockage. If repairs are necessary, have a
radiator specialist or dealer service department
perform the work, as special techniques are
required. Check the rubber mounting pads on
the bottom of the radiator (see illustration). If
they’re cracked or damaged, get new ones
before refitting the radiator.
9Bugs and dirt can be cleaned from the
radiator with compressed air and a soft brush.
Don’t bend the cooling fins as this is done.
Warning: Wear eye protection.
Refitting
10Refitting is the reverse of the removal
procedure. Be sure the rubber mounts are in
place on the bottom of the radiator.
11After refitting, fill the cooling system with
the proper mixture of antifreeze and water.
Refer to Chapter 1 if necessary.
12Start the engine and check for leaks.
Allow the engine to reach normal operating
temperature, indicated by both radiator hoses
becoming hot. Recheck the coolant level and
add more if required.
13On automatic transmission equipped
models, check and add fluid as needed and
check the power steering fluid level as well.
Expansion tank and coolant
reservoir, removal and refitting
14The expansion tank is located at the top
of the left-hand side inner wing. With the
cooling system drained below the level of the
expansion tank, remove the hoses, the
coolant level probe and the two screws
mounting it to the body (see illustration).
15Wash out and inspect the reservoir for
cracks and chafing. Renew it if damaged.16If the low-coolant level light has been
showing on the instrument panel, even when
the coolant level is correct, disconnect the
sensor’s connector and test it with an
ohmmeter (see illustration). The sensor
should be renewed if the resistance at the
connections is over 150 ohms.
Caution: Using a long-necked funnel to
add coolant can damage the sensor, which
is just below the expansion tank filler neck.
Cooling, heating and air conditioning systems 3•5
3
5.5a At the left side of the radiator,
disconnect the automatic transmission
cooler lines (small arrows) and the lower
radiator hose (larger arrow)5.5b Disconnect the power steering cooler
lines (small arrows) at the right side of the
radiator, and the upper radiator hose
(large arrow)
3261 Jaguar XJ6 5.3 Remove the clamp and the hose going
to the expansion tank
5.6 Remove the bolts (arrowed) and take
off the radiator cowl panel
5.14 The expansion tank is located on the
left inner wing
A Hose to recovery tank (where applicable)
B Hose to radiator
C Hose to thermostat housing
D Hose to water pump housing
E Mounting screws
F Low-coolant-level sensor
5.8 There are rubber mounts (arrowed)
for the radiator and the condenser -
they must be in place when these
components are reinstalled
5.16 The low-coolant-level sensor can be
tested with an ohmmeter - resistance
should be below 150 ohms - gently use a
pair of long-neck pliers to move the sensor
up and down in the tank to get a reading

10 Accelerator cable- removal,
refitting and adjustment
3
Removal
1Detach the cable from the negative terminal
of the battery.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Loosen the locknut on the threaded portion
of the throttle cable at the throttle body (see
illustration).
3Rotate the throttle lever, then slip the
throttle cable end out of the slot in the lever
(see illustration).
4Detach the throttle cable from the
accelerator pedal (see illustration).
5From inside the vehicle, pull the cable
through the bulkhead.
Refitting and adjustment
6Refitting is the reverse of removal.
7To adjust the cable, fully depress the
accelerator pedal and check that the throttle
is fully opened.
8If not fully opened, loosen the locknuts,
depress accelerator pedal and adjust the
cable until the throttle is fully open.
9Tighten the locknuts and recheck the
adjustment. Make sure the throttle closes fully
when the pedal is released (see illustration).
10After the cable is adjusted, check the
adjustment of the bellcrank. Use a small
clamp and a straight rod or stiff wire (coat
hanger) and attach it to the brake master
cylinder in such a way that the tip acts as a
pointer. Align the pointer with “A” (automatic
transmission) or “M” (manual transmission) on
the bellcrank (see illustration),depending on
what type of transmission is installed in the
vehicle.
11Slowly rotate the bellcrank until it reaches
the throttle stop (wide open throttle) andcheck to make sure the pointer aligns with the
notch in the bellcrank (see illustration).
12If necessary, adjust the position of
the throttle stop using a spanner and turn the
throttle stop screw until the bellcrank reaches
the correct position. Lock the throttle stop
screw in place.
4•8 Fuel and exhaust systems
3261 Jaguar XJ6 10.4 Remove circlip (arrowed) and separate cable from the
accelerator pedal by pulling the pin from the pedal assembly
10.2 Loosen the locknuts on the accelerator cable10.3 Rotate the bellcrank and remove the cable end from the slot
10.9 Make sure the throttle closes completely and there is a
slight amount of flex in the cable
10.10 Attach a strong wire (coat hanger)
to the master cylinder using a clamp and
align it with the notch on the bellcrank

8After the alternator is installed, adjust the
drivebelt tension (see Chapter 1).
9Check the charging voltage to verify proper
operation of the alternator (see Section 11).
13 Starting system- general
information and precautions
The sole function of the starting system is
to crank the engine over quickly enough to
allow it to start.
The starting system consists of the battery,
the starter motor, the starter solenoid, the
starter relay and the electrical circuit
connecting the components. The solenoid is
mounted directly on the starter motor.
The solenoid/starter motor assembly is
installed on the upper part of the engine, next
to the transmission bellhousing.
When the ignition key is turned to the
START position, the starter solenoid is
actuated through the starter control circuit.
The starter solenoid then connects the battery
to the starter. The battery supplies the
electrical energy to the starter motor, which
does the actual work of cranking the engine.
The starter on a vehicle equipped with an
automatic transmission can be operated only
when the transmission selector lever is in Park
or Neutral.
These vehicles are equipped with either a
Bosch or Lucas starter assembly. The Lucas
unit is distinguished by the separate earth
strap from the solenoid to the starter body.
Bosch starter assemblies are equipped with a
solid metal earthing bar.
The starting system circuit is equipped with
a relay. The relay allows the ignition switch to
power the starter solenoid.
Always observe the following precautions
when working on the starting system:
a) Excessive cranking of the starter motor
can overheat it and cause serious
damage. Never operate the starter motor
for more than 15 seconds at a time
without pausing to allow it to cool for at
least two minutes.
b) The starter is connected directly to the
battery and could arc or cause a fire if
mishandled, overloaded or short circuited.
c) Always detach the cable from the
negative terminal of the battery before
working on the starting system.
Caution:If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
14 Starter motor-
testing in vehicle
2
1Make sure that the battery is charged and
that all cables, both at the battery and starter
solenoid terminals, are clean and secure.2If the starter motor does not turn at all when
the switch is operated, make sure that the
shift lever is in Neutral or Park (automatic
transmission) or that the clutch pedal is
depressed (manual transmission).
3If the starter motor spins but the engine is
not cranking, the overrunning clutch in the
starter motor is slipping and the starter motor
must be renewed.
4If, when the switch is actuated, the starter
motor does not operate at all but the solenoid
clicks, then the problem lies with either the
battery, the main solenoid contacts or the
starter motor itself (or the engine is seized).
5If the solenoid plunger cannot be heard
when the switch is actuated, the battery is
bad, the in-line fuse is burned (the circuit is
open), the starter relay (see illustration)is
defective or the starter solenoid itself is
defective.
6To check the solenoid, connect a jumper
lead between the battery (+) and the ignition
switch terminal (the small terminal) on the
solenoid. If the starter motor now operates,
the solenoid is OK and the problem is in the
ignition switch, linear switch (1988 to 1992),
rotary switch (1993 and 1994) or in the wiring.
7If the starter motor still does not operate,
remove the starter/solenoid assembly for
dismantling, testing and repair.
8If the starter motor cranks the engine at an
abnormally slow speed, first make sure that
the battery is charged and that all terminalconnections are tight. If the engine is partially
seized, or has the wrong viscosity oil in it, it
will crank slowly.
9Run the engine until normal operating
temperature is reached, then disconnect the
coil wire from the distributor cap and earth it
on the engine.
10Connect a voltmeter positive lead to the
battery positive post and connect the
negative lead to the negative post.
11Crank the engine and take the voltmeter
readings as soon as a steady figure is
indicated. Do not allow the starter motor to
turn for more than 15 seconds at a time. A
reading of nine volts or more, with the starter
motor turning at normal cranking speed, is
normal. If the reading is nine volts or more but
the cranking speed is slow, the motor is faulty.
If the reading is less than nine volts and the
cranking speed is slow, the solenoid contacts
are probably burned, the starter motor is bad,
the battery is discharged or there is a bad
connection.
15 Starter motor-
removal and refitting
2
1Detach the cable from the negative terminal
of the battery.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Raise the vehicle and support it securely
using axle stands.
3Drain the transmission fluid (see Chapter 7)
and remove the transmission fluid filler tube
from the transmission.
4Detach the electrical connectors from the
starter/solenoid assembly (see illustrations).
5Place a trolley jack under the tail section of
the transmission, remove the rear trans-
mission mount (see Chapter 7) and lower the
transmission slightly to gain access to the
upper transmission bellhousing bolts. Using
an extension with a swivel socket, remove the
upper starter mounting bolt (see illustration).
Engine electrical systems 5•7
5
14.5 With the ignition key ON (engine not
running), check for battery voltage to the
starter relay
15.4a Disconnect the solenoid electrical
connector at the harness connector
located near the bulkhead behind the
cylinder head (arrowed)15.4b From underneath the vehicle,
remove the battery terminal from the
solenoid (cylinder head removed
for clarity)
3261 Jaguar XJ6

2The CHECK ENGINE warning light, which is
located on the instrument panel, comes on
when the ignition switch is turned to ON and
the engine is not running. When the engine is
started, the warning light should go out. If the
light remains on, the self-diagnosis system
has detected a malfunction. Note: The
CHECK ENGINE light on early models is
displayed on the dashboard VCM panel on the
right side. Later models are equipped with a
separate CHECK ENGINE light on the left side
of the instrument cluster.Note:Not all the
codes will cause the CHECK ENGINE light to
activate. When performing any fuel or
emissions systems diagnosis, always check
for codes that may be stored but not indicated
by the CHECK ENGINE light.
Obtaining fault code output
3To obtain an output of diagnostic codes,
verify first that the battery voltage is above 11
volts, the throttle is fully closed, the
transmission is in Park, the accessory
switches are off and the engine is at normal
operating temperature.
4Turn the ignition switch to ON but don’t
start the engine (Position II). Note:On 1988
and 1989 models, remember to turn the
ignition switch to position II without turning
the key to OFF.
5Press the VCM button on the display panel
(see illustration)and observe the LED display
on the dash for the designated codes. An
asterisk next to the code indicates that there
are multiple codes stored.
6The numerical values will be displayed on
the trip computer display on the dashboard.
7If there are any malfunctions in the system,
the corresponding fault codes are displayed in
numerical order, lowest to highest.
Cancelling a diagnostic code
8After the faulty component has been
repaired/renewed, the fault code(s) stored in
computer memory must be cancelled.
a) On 1988 to 1991 vehicles, simply drive
the vehicle faster than 19 mph and the
computer will automatically erase the
stored fault code from memory.b) On 1992 to 1994 models, disconnect the
negative battery lead for 30 seconds or
more to erase the stored fault codes.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
9A stored code can also be cancelled on
early models by removing the cable from the
battery negative terminal, but other items with
memory (such as the clock and radio presets)
will also be cancelled.
10If the diagnosis code is not cancelled, it
will be stored by the ECU and appear with any
new codes in the event of future trouble.
11Should it become necessary to work on
engine components requiring removal of the
battery terminal, always check to see if a
diagnostic code has been recorded before
disconnecting the battery.
4 Information sensors
Note: Refer to Chapters 4 and 5 for additional
information on the location and the diagnostic
procedures for the output actuators (ISC
motor, air supplementary valve, distributor,
amplifier, etc.) that are not directly covered in
this section.
Coolant temperature sensor
General description
1The coolant temperature sensor is a
thermistor (a resistor which varies the value of
its voltage output in accordance with
temperature changes) which is threaded into
the thermostat housing. As the sensor
temperature DECREASES, the resistance
values will INCREASE. As the sensor
Emissions and engine control systems 6•3
6
3.5 To access the self-diagnosis system
fault codes, locate the VCM button on the
dash and with the ignition key ON (engine
not running) press it to display the codes
3261 Jaguar XJ6
Fault code chart for 1988 and 1989 models
Code System affected Probable cause
1 Oxygen sensor Open oxygen sensor circuit
2 Airflow sensor Not in operating range
3 Coolant temperature sensor Not in operating range
4 Oxygen sensor System indicates full rich
5 Throttle potentiometer/airflow sensor Low throttle potentiometer signal
with high airflow sensor signal
6 Throttle potentiometer/airflow sensor High throttle potentiometer signal
with low airflow sensor signal
7 Throttle potentiometer Idle fuel adjustment failure
8 Intake air temperature sensor Open or shorted circuit in IAT sensor
harness
Fault code chart for 1990 to 1994 models
Code System affected Probable cause
11 Idle potentiometer Not in operating range
12 Airflow sensor Not in operating range
14 Coolant temperature sensor Not in operating range
16 Air temperature sensor Not in operating range
17 Throttle potentiometer Not in operating range
18 Throttle potentiometer/airflow sensor Signal resistance low
at wide open throttle
19 Throttle potentiometer/airflow sensor Signal resistance high at idle
22 Heated oxygen sensor Open or short circuit
22 Fuel pump circuit Open or short circuit
23 Fuel supply Rich exhaust Indicated
24 Ignition amplifier circuit Open or short circuit
26 Oxygen sensor circuit Lean exhaust/vacuum leak
29 ECU Self check
33 Fuel injector circuit Open or short circuit
34 Fuel injector circuit Faulty injector indicated
37 EGR solenoid circuit Short or open circuit
39 EGR circuit Faulty system operation
44 Oxygen sensor circuit Rich or lean condition
46 Idle speed control valve - (coil 1) Open or short circuit
47 Idle speed control valve - (coil 2) Open or short circuit
48 Idle speed control valve Not within specification
68 Road speed sensor Incorrect signal voltage
69 Neutral safety switch circuit Engine cranks in Drive
(adjust or renew switch)
89 Purge control valve circuit Open or short circuit

3261 Jaguar XJ6
REF•4Buying spare parts
Spare parts are available from many
sources, including maker’s appointed
garages, accessory shops, and motor factors.
To be sure of obtaining the correct parts, it
will sometimes be necessary to quote the
vehicle identification number. If possible, it
can also be useful to take the old parts along
for positive identification. Items such as
starter motors and alternators may be
available under a service exchange scheme -
any parts returned should be clean.
Our advice regarding spare parts is as
follows.
Officially appointed garages
This is the best source of parts which are
peculiar to your car, and which are not
otherwise generally available (eg, badges,
interior trim, certain body panels, etc). It is
also the only place at which you should buy
parts if the vehicle is still under warranty.
Accessory shops
These are very good places to buy
materials and components needed for themaintenance of your car (oil, air and fuel
filters, light bulbs, drivebelts, greases, brake
pads, touch-up paint, etc). Components of
this nature sold by a reputable shop are
usually of the same standard as those used
by the car manufacturer.
Besides components, these shops also sell
tools and general accessories, usually have
convenient opening hours, charge lower
prices, and can often be found close to home.
Some accessory shops have parts counters
where components needed for almost any
repair job can be purchased or ordered.
Motor factors
Good factors will stock all the more
important components which wear out
comparatively quickly, and can sometimes
supply individual components needed for the
overhaul of a larger assembly (eg, brake seals
and hydraulic parts, bearing shells, pistons,
valves). They may also handle work such as
cylinder block reboring, crankshaft regrinding,
etc.
Tyre and exhaust specialists
These outlets may be independent, or
members of a local or national chain. They
frequently offer competitive prices when
compared with a main dealer or local garage,
but it will pay to obtain several quotes before
making a decision. When researching prices,
also ask what “extras” may be added - for
instance fitting a new valve and balancing the
wheel are both commonly charged on top of
the price of a new tyre.
Other sources
Beware of parts or materials obtained from
market stalls, car boot sales or similar outlets.
Such items are not invariably sub-standard,
but there is little chance of compensation if
they do prove unsatisfactory. In the case of
safety-critical components such as brake
pads, there is the risk of financial loss, and
also of an accident causing injury or death.
Second-hand parts or assemblies obtained
from a car breaker can be a good buy in some
circumstances, but this sort of purchase is
best made by the experienced DIY mechanic.
Vehicle identification
Modifications are a continuing and
unpublicised process in vehicle manufacture,
quite apart from major model changes. Spare
parts manuals and lists are compiled upon a
numerical basis, the individual vehicle
identification numbers being essential to
correct identification of the part concerned.
When ordering spare parts, always give as
much information as possible. Quote the car
model, year of manufacture and registration,
chassis and engine numbers as appropriate.
The Vehicle Identification Number (VIN)
plate is attached to the base of the driver’s
door pillar left-hand wing valance and is
visible once the bonnet has been opened. The
vehicle identification (chassis) number is also
stamped onto a plate located inside the
windscreen and may also be stamped onto
the right-hand inner wing panel in the engine
compartment (see illustrations).
The trim code and paint codeare also
stamped onto the VIN plate.
The engine numberis stamped onto the
right-hand side of the cylinder block, next to
the distributor (see illustration).
The automatic transmission numberis
stamped onto a metal label attached to the
left-hand side of the transmission housing,
just above the sump (see illustration).The VIN is stamped on the right inner wing
panel of the engine compartment
The engine identification number is
stamped on the right side of the engine
block just behind the distributorThe transmission identification number is
located on the left side of the transmission
housing just above the sump
The VIN is also present on the left side of
the dashboard