diagram JAGUAR XJ6 1997 2.G User Guide

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

wash system, radio memory and the ABS
main feed and pump circuits.
In-line fuses are located through out the
vehicle depending on the year, make and
model. Consult the wiring diagrams at the end
of this Chapter for further information.
In-line fuses also have a blade terminal
design, which allow fingertip removal and
renewal. If an electrical component fails,
always check the fuse first. A blown fuse is
easily identified through the clear plastic
body. Inspect the element for evidence of
damage (see illustration 3.3).
Be sure to renew blown fuses with the
correct type. Fuses are usually colour-coded
to indicate their rating. Fuses of different
ratings are physically interchangeable, but
only fuses of the proper rating should be
used. Replacing a fuse with one of a different
value than specified is not recommended.
Each electrical circuit needs a specific
amount of protection. The amperage value of
each fuse is moulded into the fuse body.If the renewal fuse immediately fails, don’t
renew it again until the cause of the problem
is isolated and corrected. Don’t substitute
anything else for the fuse. In most cases, this
will be a short circuit in the wiring caused by a
broken or deteriorated wire.
5 Circuit breakers-
general information
Circuit breakers generally protect
components such as electric windows, central
locking and headlights. On some models the
circuit breaker resets itself automatically, so
an electrical overload in the circuit will cause it
to fail momentarily, then come back on. If the
circuit doesn’t come back on, check it
immediately. Once the condition is corrected,
the circuit breaker will resume its normal
function. Some circuit breakers have a button
on top and must be reset manually.To test a circuit breaker, use an ohmmeter
to check continuity between the terminals. A
reading of zero to 1.0 ohms indicates a good
circuit breaker. An open circuit reading on the
meter indicates a bad circuit breaker.
6 Relays- general information
and testing
2
General information
Several electrical accessories in the vehicle,
such as the fuel injection system, electric
windows, central locking, etc, use relays to
transmit the electrical signal to the component.
Relays use a low-current circuit (the control
circuit) to open and close a high-current circuit
(the power circuit). If the relay is defective, that
component will not operate properly. The
relays are mounted throughout the vehicle (see
illustrations). If a faulty relay is suspected, it
Body electrical system 12•3
12
3261 Jaguar XJ6 1988 to 1989 relay location details

can be removed and tested using the
procedure below or by a dealer service
department or a repair workshop. Defective
relays must be replaced as a unit.
Testing
1It’s best to refer to the wiring diagram for
the circuit to determine the proper
connections for the relay you’re testing.
However, if you’re not able to determine the
correct connection from the wiring diagrams,
you may be able to determine the test
connections from the information that follows.
2On most relays, two of the terminals are the
relay’s control circuit (they connect to the
relay coil which, when energised, closes the
large contacts to complete the circuit). The
other terminals are the power circuit (they are
connected together within the relay when the
control-circuit coil is energised).
3Relays are sometimes marked as an aid to
help you determine which terminals are the
control circuit and which are the powercircuit (see illustration). As a general rule,
the two thicker wires connected to the relay
are the power circuit; the thinner wires are
the control circuit.
4Remove the relay from the vehicle and check
for continuity between the relay power circuit
terminals. There should be no continuity.5Connect a fused jumper wire between one
of the two control circuit terminals and the
positive battery terminal. Connect another
jumper wire between the other control circuit
terminal and earth. When the connections are
made, the relay should click. On some relays,
polarity may be critical, so, if the relay doesn’t
click, try swapping the jumper wires on the
control circuit terminals.
6With the jumper wires connected, check for
continuity between the power circuit
terminals. Now, there should be continuity.
8If the relay fails any of the above tests,
renew it.
7 Direction indicator/hazard
flasher- general information
Warning: Later model vehicles
are equipped with airbags. To
prevent accidental deployment6.3 Most relays are marked on the outside
to easily identify the control circuit and
power circuits
12•4 Body electrical system
3261 Jaguar XJ6 1990 to 1992 relay location details

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

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