1997 JAGUAR XJ6 wiring

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

actuators, a control unit and associated
wiring. Diagnosis can usually be limited to
simple checks of the wiring connections and
actuators for minor faults which can be easily
repaired. Since this system uses an electronic
control unit, in-depth diagnosis should be left
to a dealership service department.
Central locking systems are operated by bi-
directional solenoids located in the doors. The
lock switches have two operating positions;
Lock and Unlock. When activated, the switch
sends a signal to the door lock control unit to
lock or unlock the doors. Depending on which
way the switch is activated, the control unit
reverses polarity to the solenoids, allowing the
two sides of the circuit to be used alternately
as the feed (positive) and earth side.
Some vehicles may have an anti-theft
system incorporated into the locks. If you are
unable to locate the trouble using the following
general paragraphs, consult a dealer service
department or other properly equipped repair
facility.
1Always check the circuit protection first.
Some vehicles use a combination of circuit
breakers and fuses.
2Operate the door lock switches in both
directions (Lock and Unlock) with the engine off.
Listen for the click of the solenoids operating.
3Test the switches for continuity. Renew the
switch if there’s not continuity in both switch
positions.
4Check the wiring between the switches,
control unit and solenoids for continuity.
Repair the wiring if there’s no continuity.
5Check for a bad earth at the switches or the
control unit.
6If all but one lock solenoid operates,
remove the trim panel from the affected door
(see Chapter 11) and check for voltage at the
solenoid while the lock switch is operated
(see illustration). One of the wires should
have voltage in the Lock position; the other
should have voltage in the Unlock position.
7If the inoperative solenoid is receiving
voltage, renew the solenoid.
8If the inoperative solenoid isn’t receiving
voltage, check for an open or short in the wire
between the lock solenoid and the control
unit. Note:It’s common for wires to break in
the portion of the harness between the body
and door (opening and closing the door
fatigues and eventually breaks the wires).26 Electric mirrors-
description and check
2
1Most electric mirrors use two motors to
move the glass; one for up and down
adjustments and one for left-right adjustments.
2The control switch has a selector portion
which sends voltage to the left or right side
mirror. With the ignition ON but the engine
OFF, roll down the windows and operate the
mirror control switch through all functions
(left-right and up-down) for both the left and
right side mirrors.
3Listen carefully for the sound of the electric
motors running in the mirrors.
4If the motors can be heard but the mirror
glass doesn’t move, there’s probably a
problem with the drive mechanism inside the
mirror. Remove and dismantle the mirror to
locate the problem.
5If the mirrors don’t operate and no sound
comes from the mirrors, check the fuse (see
Chapter 1).
6If the fuse is OK, remove the mirror control
switch from its mounting without
disconnecting the wires attached to it. Turn
the ignition ON and check for voltage at the
switch. There should be voltage at one
terminal. If there’s no voltage at the switch,
check for an open or short in the circuit
between the fuse panel and the switch.
7If there’s voltage at the switch, disconnect
it. Check the switch for continuity in all its
operating positions. If the switch does not
have continuity, renew it.
8Re-connect the switch. Locate the wire
going from the switch to earth. Leaving the
switch connected, connect a jumper wire
between this wire and earth. If the mirror
works normally with this wire in place, repair
the faulty earth connection.
9If the mirror still doesn’t work, remove the
mirror and check the wires at the mirror for
voltage. Check with ignition ON and the mirror
selector switch on the appropriate side.
Operate the mirror switch in all its positions.
There should be voltage at one of the switch-
to-mirror wires in each switch position (except
the neutral “off” position).
10If there’s not voltage in each switch
position, check the circuit between the mirror
and control switch for opens and shorts.
11If there’s voltage, remove the mirror and
test it off the vehicle with jumper wires. Renew
the mirror if it fails this test.
27 Electric sunroof-
description and check
2
1The electric sunroof is powered by a single
motor in the roof behind the overhead console.
The power circuit is protected by a fuse.
2The control switches (tilt and slide) send an
earth signal to the sunroof motor when theswitches are pressed. Power is supplied to
the motor from the relay. With the ignition ON
but the engine OFF, operate the sunroof
control switch through the tilt and slide
functions.
3Listen carefully for the sound of the sunroof
motor running in the roof.
4If the motors can be heard but the sunroof
glass doesn’t move, there’s probably a
problem with the drive mechanism or drive
cables.
5If the sunroof does not operate and no
sound comes from the motor, check the fuse
(see Chapter 1).
6If the fuse is OK, remove the control
switches (see Chapter 11). Disconnect the
wires attached to it. Turn the ignition ON and
check for voltage at the switch. If there’s no
voltage at the switch, check for power and
earth at the motor. If power and earth exist at
the motor and there’s still no voltage at the
switch renew the motor. If there’s no voltage
at the motor, check the relay or an open or
short in the wiring between the relay and the
motor.
7If there’s voltage at the switch, disconnect
it. Check the switch for continuity in all its
operating positions. If the switch does not
have continuity, renew it.
8If the switch has continuity re-connect the
switch. Locate the wire going from the switch
to earth. Leaving the switch connected,
connect a jumper wire between this wire and
earth. If the motor works normally with this
wire in place, repair the faulty earth
connection.
9The sunroof can be closed manually by
inserting the T-handle spanner which is
located inside the overhead console. Insert
the spanner into the motor drive shaft and
rotate the shaft clockwise (see illustration).
28 Airbag system-
general information
Warning: Failure to follow these
precautions could result in
accidental deployment of the
airbag and personal injury.
12•14 Body electrical system
25.6 Check for voltage at the lock
solenoid while the lock switch is operated27.9 To close the sunroof manually, insert
the T-handle spanner in the motor shaft
and rotate it clockwise
3261 Jaguar XJ6

Later models are equipped with a
Supplemental Restraint System (SRS), more
commonly known as an airbag. This system is
designed to protect the driver, and on 1994
models, the passenger from serious injury in
the event of a head-on or frontal collision. It
consists of an airbag module in the centre of
the steering wheel and a passenger airbag
module on the right side of the dash above
the glove box on 1994 models.
The airbag modules contain an inflater and
a sensor assembly which activates from
impact energy that is transmitted through the
body and steering column upon impact or
collision.
DO NOT try to dismantle or remove any
component in the vicinity of the steering
column or instrument panel on models
equipped with air bags. Serious personalinjury or damage may result. The
manufacturer recommends that, on airbag
equipped models, service which requires
removal of any component in the vicinity of
the instrument panel or steering column
should be left to a dealer service department
or other properly equipped repair facility
because of the special tools and techniques
required to disable the air bag system.
29 Wiring diagrams-
general information
Since it isn’t possible to include a complete
wiring diagram for every year covered by this
manual, the following diagrams are those that
are typical and most commonly needed.Prior to diagnosing any circuits, check the
fuse and circuit breakers (if equipped) to make
sure they are in good condition. Make sure
the battery is properly charged and has clean,
tight cable connections (see Chapter 1).
When checking the wiring system, make
sure that all electrical connectors are clean,
with no broken or loose pins. When
unplugging an electrical connector, do not
pull on the wires, only on the connector
housings themselves.
Body electrical system 12•15
12
3261 Jaguar XJ6 Wiring diagrams commence overleaf

12•16 Wiring diagrams
3261 Jaguar XJ6
Typical 1988 to 1992 starting and charging system
Typical 1993 and 1994 starting and charging system

Wiring diagrams 12•17
12
3261 Jaguar XJ6
Typical 1988 to 1992 engine management system

12•18 Wiring diagrams
3261 Jaguar XJ6
Typical 1993 and 1994 engine management system

Wiring diagrams 12•19
12
3261 Jaguar XJ6
Typical engine cooling fan system
Typical 1988 instrument warning light system

12•20 Wiring diagrams
3261 Jaguar XJ6
Typical 1989 to 1994 instrument warning light system