1997 JAGUAR XJ6 cruise control

8Tighten the screws to the torque listed in
this Chapter’s Specifications in three or four
equal steps.
9Refit the remaining components, start the
engine and check for oil leaks.
5 Intake manifold-
removal and refitting
2
Removal
1Disconnect the negative cable from 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.
2Refer to Chapter 4 to remove the
accelerator and cruise-control linkage, safely
relieve the fuel system pressure, and
disconnect the fuel supply lines.
3Label or mark and detach the PCV and
vacuum hoses connected to the intake
manifold, (see illustration).
4The intake manifold can be removed with
the injectors and fuel rail still in place.
Disconnect the electrical connectors at
each injector (label them first for reassembly).
If the injectors are to be removed from the
intake manifold, refer to Chapter 4.
5Refer to Chapter 4 and remove the throttle
body.6Remove the three nuts retaining the oil filler
tube bracket, then pull the tube up as far as
possible (see illustrations).
7Remove the ground strap and intake
manifold mounting nuts/bolts, then detach the
intake manifold from the engine (see
illustrations).
Refitting
8Clean the mating surfaces of the intake
manifold and the cylinder head mounting
surface with lacquer thinner or acetone. If the
gasket shows signs of leaking, have the
manifold checked for warpage at an
automotive machine workshop and
resurfaced if necessary.
9Refit a new gasket, then position the intake
manifold on the cylinder head and refit the
nuts/bolts (see illustration).
10Tighten the nuts/bolts in three or four
equal steps to the torque listed in this
Chapter’s Specifications. Work from the
centre out towards the ends to avoid warping
the manifold.
11Refit the remaining parts in the reverse
order of removal.
12Before starting the engine, check the
throttle linkage for smooth operation.
13Run the engine and check for coolant and
vacuum leaks.
14Road test the car and check for proper
operation of all accessories, including the
cruise control system.
6 Exhaust manifolds-
removal and refitting
2
Warning: The engine must be
completely cool before beginning
this procedure.
Removal
1Disconnect the negative cable from 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.
2On 1990 and later models, disconnect the
EGR pipe and remove the EGR valve from the
top of the exhaust manifold (see Chapter 6).
3Apply penetrating oil to the exhaust
manifold mounting nuts/bolts, and the nuts
retaining the exhaust pipes to the manifolds.
After the nuts have soaked, remove the nuts
retaining the exhaust pipes to the manifolds
and the lower bolt from the heat shield (see
illustration).
4Remove the heat shield from the exhaust
manifolds(see illustration).
5Disconnect the electrical connector to the
oxygen sensor. Unless the oxygen sensor is
being renewed, leave the sensor in place.
6Remove the nuts/bolts and detach the
manifolds and gaskets (see illustration).
2A•4 Engine in-car repair procedures
5.3 The various hoses should be marked
to ensure correct refitting5.6a Remove the oil filler tube bracket
nuts (arrowed) . . .5.6b . . . pull the tube up to dislodge it
from the housing - it won’t come out, but
can be removed with the intake manifold
5.7a Remove the ground strap from the
front stud (arrowed), and the engine wiring
harness clips from the other studs5.7b Remove the intake manifold bolts/
nuts and remove the intake manifold - the
upper fasteners are studs/nuts, while the
lower row are bolts (two arrowed)5.9 Refit the new intake manifold gasket
over the studs (arrowed) refit the manifold
3261 Jaguar XJ6

3Remove the screws holding the cruise-
control ECU in place (see illustrations), then
remove the four screws holding the ECU
mounting plate in place.
4Disconnect the vacuum lines and electrical
connectors at the blower housing, identifying
each connection with marked masking tape
for reassembly, or write down the colour
codes of the vacuum tubing. Remove the duct
tape connecting the blower housing to the
duct from the heater/air conditioning unit.
5Remove the two bolts holding the top of the
blower housing to the cowl (see illustration).
6Pull down and back on the housing until itsqueezes past the metal brace below it (see
illustration).It will take some force at first.
7To access the left blower motor, remove
the left-hand brace rod from the steering
column forward to the body(see illustration),
then repeat Steps 4 and 5 on the left blower
housing. The blower housing should now drop
straight down and out.
8If the blower motor does not operate,
disconnect the electrical connectors at the
blower motor and connect the black wire
terminal to chassis ground, and the purple
wire terminal to a fused source of battery
voltage. If the blower doesn’t operate, itshould be renewed. If it does operate, there is
a problem in the feed or earth circuit.
9If the motor is good, but doesn’t operate at
any speed, the problem could be in the
heater/air conditioning control assembly or
the heating/air conditioning computer.
Diagnosis either of these electronic com-
ponents is beyond the scope of the home
mechanic, and should be referred to your
Jaguar dealer or other qualified repair facility.
10If either blower motor must be renewed,
remove the five clips and one screw holding
the blower housing halves together (see
illustration).
3•8 Cooling, heating and air conditioning systems
10.2a The right blower housing (arrowed)
is located behind the glove box area
of the dash10.2b Apply heavy duct tape to the sharp
edge of this brace (dotted line) when
working behind the glove box area of the
dash - the metal is very sharp10.3a Remove the screw (A) holding the
wiring harness in place, then remove the
two lower cruise-control ECU screws (B) . . .
10.3b . . . then remove the upper ECU
screw (arrowed) and pull down the ECU,
then remove the ECU mounting plate10.5 Two bolts (arrow indicates the left
bolt) hold the top of the blower housing
to the cowl10.6 Pull down and out on the housing
until it clears the sheet metal brace
below it
3261 Jaguar XJ6 10.7 Remove this brace rod (small arrow)
for clearance to remove the left blower
motor housing (large arrow)
10.10 Remove the five clips (two shown
here with arrows) and one screw holding
the halves of the housing together

bulbs (open-circuit between the switch and
the bulbs), or the switch is defective.
5To remove the switch, reach up under the
dash and unplug the two electrical connectors
- one for the brake lights and one for the
cruise control system. Locate the two pairs of
leads coming down the pedal box and trace
them to their connectors on or near the
steering column.
6Remove the three switch-plate retaining
bolts and remove the switch assembly (see
illustrations). Inspect the switch-plate rubber
gasket for cracks or deterioration and renew it
if it’s damaged or worn.
7Place the switch assembly on a workbench
and connect an ohmmeter to the brake lightswitch terminals. With the switch plunger in its
normal, extended position (brake pedal not
applied), there should be no continuity (infinite
resistance) (see illustration); when the
plunger is depressed (brake pedal applied),
there should be continuity (zero resistance)
(see illustration). If the switch doesn’t
perform as described, renew it. If the switch
works in an opposite fashion, i.e. continuity
when the plunger is free, no continuity when
the plunger is depressed, you’ve tested the
cruise control switch! Switch the ohmmeter
leads to the other connector and recheck.
8To remove the switch from the plate,
remove the two small nuts on the back of the
plate (see illustration).9Refit the switch assembly and the switch
plate bolts but don’t tighten the bolts yet.
10Plug in the brake light and cruise control
connectors.
11The holes in the switch plate are slotted
for adjustment. While an assistant presses the
brake pedal, verify that the brake lights come
on; with the pedal released, make sure the
brake lights are off. If the lights don’t come on
when the pedal is depressed, or stay on when
the pedal is released, adjust the switch by
moving the plate until proper operation is
achieved. Tighten the switch-plate bolts.
12After tightening the switch-plate bolts,
check the switch again to make sure it
performs properly.
9•14 Braking system
13.6a To remove the brake light switch,
remove the three mounting plate screws
(arrowed) . . .13.6b . . . and carefully pry the switch plate
away from the pedal box - be careful not to
damage the gasket13.7a To check the brake light switch,
connect an ohmmeter to the switch
terminals; with the switch plunger
released, there should be no continuity
(infinite resistance)
13.7b With the switch plunger depressed,
there should be continuity
(zero resistance)13.8 If you’re replacing the switch, remove
these two nuts (arrowed) and transfer the
retaining plate to the new switch
3261 Jaguar XJ6

3261 Jaguar XJ6
12
Chapter 12
Body electrical system
1 General information
The electrical system is a 12-volt, negative
earth type. Power for the lights and all
electrical accessories is supplied by a
lead/acid-type battery which is charged by
the alternator.
This Chapter covers repair and service
procedures for the various electrical
components not associated with the engine.
Information on the battery, alternator,
distributor and starter motor will be found in
Chapter 5.
It should be noted that when portions of the
electrical system are serviced, the cable
should be disconnected from the negative
battery terminal to prevent electrical shorts
and/or fires.
2 Electrical fault finding-
general information
A typical electrical circuit consists of an
electrical component, any switches, relays,
motors, fuses, fusible links, in-line fuses or
circuit breakers related to that component
and the wiring and electrical connectors that
link the component to both the battery andthe chassis. To help you pinpoint an electrical
circuit problem, wiring diagrams are included
at the end of this Chapter.
Before tackling any troublesome electrical
circuit, first study the appropriate wiring
diagrams to get a complete understanding of
what makes up that individual circuit. Trouble
spots, for instance, can often be narrowed
down by noting if other components related to
the circuit are operating properly. If several
components or circuits fail at one time,
chances are the problem is in a fuse or earth
connection, because several circuits are often
routed through the same fuse and earth
connections.
Electrical problems usually stem from
simple causes, such as loose or corroded
connections, a blown fuse, a melted fusible
link or a bad relay. Visually inspect the
condition of all fuses, wires and connections
in a problem circuit before diagnosing it.
If testing instruments are going to be
utilised, use the diagrams to plan ahead of
time where you will make the necessary
connections in order to accurately pinpoint
the trouble spot.
The basic tools needed for electrical fault
finding include a circuit tester or voltmeter (a
12-volt bulb with a set of test leads can also
be used), a continuity tester, which includes a
bulb, battery and set of test leads, and a
jumper wire, preferably with a circuit breaker
incorporated, which can be used to bypasselectrical components. Before attempting to
locate a problem with test instruments,
use the wiring diagram(s) to decide where to
make the connections.
Voltage checks
Voltage checks should be performed if a
circuit is not functioning properly. Connect
one lead of a circuit tester to either the
negative battery terminal or a known good
earth. Connect the other lead to a electrical
connector in the circuit being tested,
preferably nearest to the battery or fuse. If the
bulb of the tester lights, voltage is present,
which means that the part of the circuit
between the electrical connector and the
battery is problem free. Continue checking the
rest of the circuit in the same fashion. When
you reach a point at which no voltage is
present, the problem lies between that point
and the last test point with voltage. Most of
the time the problem can be traced to a loose
connection. Note:Keep in mind that some
circuits receive voltage only when the ignition
key is in the Accessory or Run position.
Finding a short
One method of finding shorts in a circuit is
to remove the fuse and connect a test light or
voltmeter in its place. There should be no
voltage present in the circuit. Move the wiring
harness from side to side while watching the
test light. If the bulb goes on, there is a short Airbag system - general information . . . . . . . . . . . . . . . . . . . . . . . . . 28
Bulb renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Central locking system - description and check . . . . . . . . . . . . . . . . 25
Circuit breakers - general information . . . . . . . . . . . . . . . . . . . . . . . . 5
Cruise control system - description and check . . . . . . . . . . . . . . . . . 23
Direction indicators/hazard flashers - general information . . . . . . . . 7
Electric aerial - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 14
Electric side view mirrors - description and check . . . . . . . . . . . . . . 26
Electric sunroof - description and check . . . . . . . . . . . . . . . . . . . . . . 27
Electric window system - description and check . . . . . . . . . . . . . . . 24
Electrical fault finding - general information . . . . . . . . . . . . . . . . . . . 2
Fuel, oil and temperature gauges - check . . . . . . . . . . . . . . . . . . . . . 11
Fuses - general information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Headlight housing (1992 to 1994 models) - removal and refitting . . . 19Headlights - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Headlights - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Heated rear window - check and repair . . . . . . . . . . . . . . . . . . . . . . 16
Horn - check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Ignition switch and key lock cylinder - removal and refitting . . . . . . 9
Inertia switch - description and check . . . . . . . . . . . . . . . . . . . . . . . . 22
In-line fuses - general information . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Instrument cluster - removal and refitting . . . . . . . . . . . . . . . . . . . . . 12
Instrument panel switches - removal and refitting . . . . . . . . . . . . . . 10
Radio and speakers - removal and refitting . . . . . . . . . . . . . . . . . . . 13
Relays - general information and testing . . . . . . . . . . . . . . . . . . . . . . 6
Steering column switches - removal and refitting . . . . . . . . . . . . . . . 8
Windscreen wiper motor - removal and refitting . . . . . . . . . . . . . . . . 15
Wiring diagrams - general information . . . . . . . . . . . . . . . . . . . . . . . 29
12•1
Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

23 Cruise control system-
description and check
5
1The cruise control system maintains vehicle
speed with an independently operated vacuum
motor located on the passenger’s side inner
wing in the engine compartment. When the
cruise control switch is turned on, a vacuum
actuator (connected the throttle linkage) is
activated by vacuum from the vacuum motor.
The system consists of the vacuum motor,
vacuum actuator, brake switch, control
switches, a relay and associated vacuum
hoses. Some features of the system require
special testers and diagnostic procedures
which are beyond the scope of this manual.
Listed below are some general procedures that
may be used to locate common problems.
2Locate and check the fuse (see Section 3).
3Have an assistant operate the brake lights
while you check their operation (voltage from
the brake light switch deactivates the cruise
control).
4If the brake lights don’t come on or don’t
shut off, correct the problem and re-test the
cruise control.
5Visually inspect the vacuum hose
connected to the vacuum motor and vacuum
actuator. Check the freeplay between the
vacuum actuator stop and the throttle link slot
(see illustration).
6Test drive the vehicle to determine if the
cruise control is now working. If it isn’t, take it
to a dealer service department or an
automotive electrical specialist for further
diagnosis and repair.
24 Electric window system-
description and check
2
1The electric window system operates
electric motors, mounted in the doors, which
lower and raise the windows. The system
consists of the control switches, relays, the
motors, regulators, glass mechanisms and
associated wiring.
2The electric windows can be lowered and
raised from the master control switch by the
driver or by remote switches located at the
individual windows. Each window has a
separate motor which is reversible. The
position of the control switch determines the
polarity and therefore the direction of
operation.
3The circuit is protected by a fuse. Each
motor is also equipped with an internal circuit
breaker, this prevents one stuck window from
disabling the whole system.
4The electric window system will only
operate when the ignition switch is ON. In
addition, many models have a window lockout
switch at the master control switch which,
when activated, disables the switches at the
rear windows and, sometimes, the switch at
the passenger’s window also. Always check
these items before diagnosing a window
problem.
5These procedures are general in nature, so
if you can’t find the problem using them, take
the vehicle to a dealer service department or
other properly equipped repair facility.
6If the electric windows won’t operate,
always check the fuse first.
7If only the rear windows are inoperative, or
if the windows only operate from the master
control switch, check the rear window lockout
switch for continuity in the unlocked position.
Renew it if it doesn’t have continuity.
8Check the wiring between the switches andfuse panel for continuity. Repair the wiring, if
necessary.
9If only one window is inoperative from the
master control switch, try the other control
switch at the window. Note:This doesn’t
apply to the driver’s door window.
10If the same window works from one
switch, but not the other, check the switch for
continuity.
11If the switch tests OK, check for a short or
open in the circuit between the affected
switch and the window motor.
12If one window is inoperative from both
switches, remove the trim panel from the
affected door and check for voltage at the
switch and at the motor while the switch is
operated (see illustration).
13If voltage is reaching the motor,
disconnect the glass from the regulator (see
Chapter 11). Move the window up and down
by hand while checking for binding and
damage. Also check for binding and damage
to the regulator. If the regulator is not
damaged and the window moves up and
down smoothly, renew the motor. If there’s
binding or damage, lubricate, repair or renew
parts, as necessary.
14If voltage isn’t reaching the motor, check
the wiring in the circuit for continuity between
the switches and motors. You’ll need to
consult the wiring diagram for the vehicle.
If the circuit is equipped with a relay, check
that the relay is earthed properly and receiving
voltage.
15Test the windows after you are done to
confirm proper repairs.
25 Central locking system-
description and check
5
The central locking system operates the
door lock actuators mounted in each door.
The system consists of the switches, relays,
Body electrical system 12•13
12
3261 Jaguar XJ6 23.5 Check the cruise control throttle linkage for binding
24.12 If no voltage is present at the motor with the switch
depressed, check for voltage at the switch

Wiring diagrams 12•29
12
3261 Jaguar XJ6
Typical 1988 to 1990 cruise control system
Typical 1991 and 1992 cruise control system

12•30 Wiring diagrams
3261 Jaguar XJ6
Typical 1993 and 1994 cruise control system

3261 Jaguar XJ6
REF•22Index
AABS fault finding -9•2
Accelerator cable -4•8
Acknowledgements -0•4
Aerial - 12•8
Air cleaner -1•14, 4•7
Air conditioning -3•2, 3•7, 3•10, 3•11, 3•13, 3•14
Air induction system -4•9
Air Injector Reactor (AIR) system -6•8
Air intake plenum -4•13
Airbag - 0•5, 12•14
Alternator -5•6
Amplifier -5•3
Anti-lock Brake system (ABS) -9•2
Anti-roll bar - 10•3
Anti-theft system - REF•1
Antifreeze -0•11, 0•16, 1•2, 1•20, 3•2
Asbestos -0•5
ATF -0•16
Automatic transmission-7•1et seq
fault finding - 7•1, REF•15
fluid - 0•16, 1•2, 1•11, 1•19
filter - 1•19
Auxiliary shaft -2A•8
BBalljoints - 10•4
Battery -0•5, 0•15, 1•9, 5•1, 5•1
Big-end bearings -2B•13, 2B•17
Bleeding
brake system - 9•10
power steering - 10•11
Block -2B•10, 2B•11
Blower motors -3•7
Body corrosion - REF•11
Body electrical system- 12•1et seq
Bodywork and fittings- 11•1et seq
Bonnet - 11•3, 11•4
Boot - 11•7
lid - 11•3, 11•6, 11•7,
Boots (steering) - 10•9
Brake fluid -0•12, 0•16, 1•20
Brake lights - 12•12
switch - 9•13
Brake servo -1•12
Braking system-1•12, 9•1et seq
fault finding - REF•15, REF•16
MOT checks - REF•8 to REF•10
Bulbs -0•15, 12•11
Bumpers - 11•5
Burning -0•5
CCables -4•8, 5•2, 7•2, 7•4, 9•10, 9•11, 11•4, 11•10
Calipers -9•3
Camshafts -2A•9
Capacities -1•2
Carpets - 11•1
Cassette - REF•1
Catalytic converter -6•12
Central locking - 12•13
Centre console - 11•11
Charcoal canister -6•11
Charging -1•10
Charging system -5•5
Circuit breakers - 12•3
CO emissions (mixture) - REF•11
Coil (HT) -5•3
Coil spring - 10•5, 10•6
Compression check -2B•3
Compressor -3•13
Condenser -3•13
Connecting rods -2B•9, 2B•12, 2B•17, 2B•18
Console - 11•11, 11•12
Continuity check - 12•2
Control arms - 10•5, 10•6, 10•8
Conversion factors - REF•2
Coolant -0•11, 0•16, 1•2, 1•20, 3•2
Coolant reservoir -3•4, 3•5
Coolant temperature sensor -6•3
Cooling fans -3•3
Cooling system fault finding - REF•14
Cooling,heating and air conditioning systems-3•1et seq
Courtesy lights - 12•12
Cowl cover - 11•14
Crankcase ventilation system -1•16, 6•11
Crankshaft -2A•5, 2A•17, 2B•10, 2B•13, 2B•16
position sensor - 6•7
Cruise control - 12•13
Crushing -0•5
Cylinder head -2A•13, 2B•6, 2B•7, 2B•8
Cylinder honing -2B•12
DDashboard - 11•13
Dents - 11•2
Differential -8•1, 8•5
oil - 1•2, 1•11, 1•20
Dimensions - REF•1
Direction indicators - 12•4, 12•11, 12•12
Discs -9•4
Distributor -5•4
Doors - 11•7, 11•8, 11•9, 11•10, 11•10, REF•9
Drivebelt -1•16
Driveplate -2A•16
Driveshafts -8•1, 8•4, 8•5, REF•10
Drivetrain-1•14, 8•1et seq
Note:References throughout this index are in the form - “Chapter number” • “page number”