Jaguar XJ-S

Schematic Drawings

http://www.skjagtech.co.uk

1975 -1991

Pre facelift models

Copyright (c) S&K Jagtech (skjagtech.co.uk) 2005

Document dated 15-May-2006

Head, Side lights

3

Fog light

3

Headlamp wash wipe

4

Cruise Control

4

Wash wipe

5

Radio

6

Merlin and Hirschmann

6

Boot lights

6

Flasher indicators

7

Window lift

7

Interior Lights

8

Bulb failure

8

Door Lock/Unlock Lucas

9

Door Lock/Unlock Kiekerk

9

Small items

10

Trip Computer

11

Intruments

11

Electrically operated door mirrors

12

Heated backlight

12

Heated Drivers Seat and Lumbar control

13

Quad headlamps

13

Boot Lock/Unlock

14

TWR/JaguarSport Ariel Arrest

14

Jaguar XJ-S Window Lift with 4 relay upgrade and Negitive rest

15

Jaguar XJ-S Wiper under relay control

16

DISCLAIMER

Should you decide to undertake work on any system covered in these documents, SK Jagtech accept no
liability for damage to the vehicle or personal injuries however caused. The information in this
document is provided to help explain and provided reference material.
We are geared up with the right equipment and have trained knowledgeable staff who can perform
maintenance and fault finding on your Jaguar and it is recommend that you leave any technical work
to a suitable specialist firms if you are in any way unsure of a procedure. You are always welcome
to contact us for advice.

Contents

Main

Switch

Headlamp inhibit relay

Main relay

Headlamp
flash

Fog lamp switch

Fuse 1

Fuse 5

Fuse 3

Fuse 4

Fuse 2

Dip Beam

R/H

L/H

R/H

L/H

Main Beam

Front Fog lamps

Rear Fog Lamps

R/H

L/H

R/H

L/H

R/U

R/Y

R/O

N

R/U

U/R

U

U/W

Main beam

warning

lamp

Fog lamp

warning

lamp

Terminal post

N

U

To Stop lamp
failure unit

To Caravan Socket

To Caravan Socket

R/H

L/H

No plate

Rear tail

No plate

Rear tail

F parking L/H

F parking R/H

Switch and
Clock Lamps

Panel Lamps

Fibre Optic Lamp

Cigar lighter

Gearbox selector

Bulb Failure lamp

Warning lamp blocking diodes

Rheostat

Fuse 7

Bulb failure

unit front

Bulb failure

unit left rear

Bulb failure

unit right rear

Rear lamp in-line fuse

Rear lamp in-line fuse

Fuse 15

Fuse 14

Side marker

NAS

Side marker

NAS

Alternative to

computer harness

if fitted

Latched

Dip

Main

Generic Diagram

Different models are cabled
differently and therefore this
diagram is a generic curcuit
that should help trace a fault.

As data becomes available
we will add additional diagrams
to cover the differences in
switch gear extra

Jaguar XJ-S Head, Side and Fog light Schematic

3

Y

BR

YW

YB

NW

N

G

N

NB

NY

BK

YP

B

BS

YB

YW

GP

YO

YO

BG

LGY

G

BW

B

B

LGW

G

YW

Wiper Motor Right

Wiper Motor Left

Transducer

Speed Control
Interface ECU

Bellows and actuator solenoid valves

Wash Wipe Relay

LG

U

LG

BW To headlight
main beam

UR To headlight
Dip beam

Diode Pack
Pektron Blue

Windscreen
Washer Pump

Headlight
washer
pump

LGU

Washer switch

Brake Operated switch

Control Switch

Fuse 17

Set Switch

Inhibit Switch

Kickdown Solenoid

Kickdown Switch

To fuse 5

To fuse 4
via control
module in
Boot/trunk
harness

1

2

3

4

5

Jaguar XJ-S Headlamp wash wipe and Cruise Control Schematic

4

A

B

C

D

1

2

3

4

5

6

7

Wiper Motor

Park

Run

LG

OLG

ULG

RLG

WLG

BLG

A

Intermittent/
flick wipe

7-3-1 & 5-6

B

Fast Wipe

1-4 & 27

C

Slow Wipe

1-5 & 2-7

D

Off

1-7 and 5-6

Switch Schematic explained

This is a Jaguar idea here (don’t blame us)
The black lines A, B, C and D are used to
show which contacts 1-7 are conected in
which ever mode is in use.
For example
Slow=1-5 and 2-7 Fast=1-4 and 2-7
Below are two other variations 1 designed by us
which are provided to get the point across

Off/Park

Slow

Fast

Intermitant

W/LG

B/LG

K/LG

LG/B

B

U/LG

R/LG

LG

W/LG

B/LG

K/LG

LG/B

B

U/LG

R/LG

LG

W/LG

B/LG

K/LG

LG/B

B

U/LG

R/LG

LG

W/LG

B/LG

K/LG

LG/B

B

U/LG

R/LG

LG

Off/Park

Slow

Fast

Intermitant

Fuse 9

Dela

y Unit

Jaguar XJ-S wash wipe and heated backlight Schematic

5

Jaguar XJ-S Radio, Merlin and Hirschmann Aerial Schematic

Radio - CD/Tape

Aerial

Delay relay unit

Boot Lights

BS

NP

Clock where fitted

In Line Fuse

WK

WK

UW

UR

3

5

1

2

4

Merlin Style Electric Aerial

Radio - CD/Tape

Aerial

Delay relay unit

Boot Lights

BS

NP

Clock where fitted

In Line Fuse

WK

WK

W/O

P

3

5

1

2

4

Hirschmann Style Electric Aeriel

30/51

87

86

85

87a

Omiting Mast Delay

For those who don’t want the 10 sec delay for the
mast to retract or who have a faulty delay module:
Substitute with a change over relay (Part no REL7DB
available from us) and wire it in as per the relay
schematic shown in fig 1. Note that the pin configuration
is different on a standard ISO relay than on the Lucas
delay module, fig 2.

Fig 2 Lucas with
ISO numbering

30/51

87

86

87a

Fig 1

30/51

87

86

85

87a

Omiting Mast Delay

For those who don’t want the 10 sec delay for the
mast to retract or who have a faulty delay module:
Substitute with a change over relay (Part no REL7DB
available from us) and wire it in as per the relay
schematic shown in fig 1. Note that the pin configuration
is different on a standard ISO relay than on the Lucas
delay module, fig 2.

Fig 2 Lucas with
ISO numbering

30/51

87

86

87a

Fig 1

No connection

85

85

6

Jaguar XJ-S Flasher indicators and window lift Schematic

Hazard Switch

Flasher Unit

Flasher Switch

Blocking diode

LH Warning Lamp

Blocking diode

RH Warning lamp

RH repeater

RH Front indicator

RH Rear indicator

LH repeater

LH Front indicator

LH Rear indicator

Hazard warning lamp

Fuse 2

To terminal post

To fuse 5

Acoustic unit

Caravan Socket

Caravan Socket

B

B

GW

GN

LGB

LGU

LGP

NO

LGU

G

LGN

LH Window lift switch

LH Window motor

RH Window lift switch

RH Window motor

RG

GR

RU

GU

B

B

B

NU

NU

NU

N

WK

To Terminal post

To Ignition

Window Lift relay

Thermal Switch

UNKNO

WN

1

2

3

6

7

8

1

2

3

6

7

8

Up

Rest

Down

1

2

3

6

7

8

1

2

3

6

7

8

1

2

3

6

7

8

Pins 1&3 -

Pins 2&6 +

Pins 1&3 +
Pins 2&6 +

Pins 1&3 +

Pins 2&6 -

Switch motion

and yes for some bizare reason

known only to the engineers at Lucas the motor
is live on both sides at rest.

7

Jaguar XJ-S Interior Lights and Bulb failure Schematic

Map Light Switch

Interior Light Switch

Roof Light and Switch

Fuse 13

To Terminal Post

Delay

unit

LH Door

Switch

RH Door

Switch

Blocking

Diode

Puddle Lamp

Rear

Passenger

lamp

Puddle Lamp

Rear

Passenger

lamp

Drivers Lamp

Passenger Lamp

PG

PWS

P

PK

PW

PW

P

PK

PWS

Warning Lamp

Failure Unit

Reservoir brake switch

PDWA

Brake

Warning

Lamp

Oxygen Warning

Lamp

Handbrake

Warning

Lamp

Handbrake
Switch

Stop Lamp failure Warning Unit

RH Stop Lamp

To Ignition Switch

LH Stop Lamp

To Bulb Failure unit via diode

To Foot Brake Switch

To Stop Lamp bulb failure unit

BS

WY

B

WY

B

GP

LGP

BY

B

W

BW

BW

BY

BY

BS

NOTE: This diagram is full of factory drawing errors

(awaiting correction by S&K Jagtech)

8

Jaguar XJ-S Door Lock/Unlock Lucas and Kiekerk Schematic

LOCK

UNLOCK

L/H

R/H

FOR BOOT LOCK MOD

see Upgrades Schematics

L/H

R/H

Actuators (LUCAS SYSTEM)

OR

OG

OG

OR

OW

NR

N

P

N

B

B

B

B

B

OU

O/B

O/R

O/W

O/G

B

N

P

N

O/R

O/B

O/W

O/G

O/W

O/G

Control Module

To terminal 12v supply

To terminal 12v supply

Thermal breaker

L/H Door Motor

R/H Door Motor

Boot / Trunk Motor

W

Grounded through Solinoid body

9

Jaguar XJ-S Small item Schematic

Fuse 4

Warning

Light

Control

Unit

Low Coolant

Warning Lamp

Coolant Temp

Sensor

To Ignition switch

G

WU

B

WR

B

WU

W

WR

Coolant warning Schematic

Vacuum Delay

Schematic

Overcharge

Schematic

To Aircon

To Fuse 11

To Fuse 1

Delay Unit

2

3

4

5

2 3 way solenoid valve
3 2 way solenoid valve
4 Solenoid air valve
5 Coolant temp Switch

To Positive

Supply

Warning Light

Control

Unit

To Ignition

Switch

PW

NS

BS

B

B

B

B

B

B

Logic Unit

Seat Belt Warning Schematic

B

To fuse 2

NR

PG To Door Switch

W To ignition sw

GO

K

Horn Sw

To Fuse 11

Hor n Relay

Hor n

Hor n

LG

PY

B

N

PY

Coolant Fan

In Line Fuse

Diode pack

GN

GN

LG

BG

BG

LG

GN

Aircon Cooling Fan Schematic

Horn Schematic

A

C Clutc

h

T

her
mo

switc

h

10

Transducer

10:30

Terminal Post

To Sidelamps

To fuse 4

To ECU pin 26

To Speedometer

Connector

Trip Computer

YG

O

B

G

YB - Y

Y

B

P

RU

G

YG

G

Jaguar XJ-S Trip Computer Schematic and Intruments

Interface

Unit

Connector

G

B

GU

WN

LGO

WS

To fuse 4

Temperature

Oil pressure

Fuel

Battery

Tachometer

To Amplifier

To ignition switch

Low fuel warning

Fuel
tank

sender

Oil

pressure

transmitter

Coolant

temperature

sender

w

WS

11

Jaguar XJ-S Electrically operated door mirrors and heated backlight

PNS

PKS

PUS

PGS

PNS

PKS

PUS

PGS

To Fuse 8

To Fuse 8

RH mirror switch

RH Vertical Motor

RH Horizontal Motor

LH mirror switch

LH Vertical Motor

LH Horizontal Motor

LH Door Mirror

Backlight

RH Door Mirror

Warning Lamp

Control Switch

Delay Unit

Fuse 12

To Ignition switch
protection Relay

12

Jaguar XJ-S Heated Drivers Seat and Lumbar control & Quad headlamps

Fuse 14

Fuse 13

Fuse 20

Fuse 19

To Ignition Switch

To Battery +12v Terminal post

Seat relay (5 pin)

Heater Timer

Heater Timer

Lumber Motor

Lumber Motor

Heater Element

Heater Element

Left Hand

Right Hand

Main relay

Headlamp
flash

Fuse 5 20a

Fuse 3 20a

Fuse 4 35a

Fuse 2 35a

Dip Beam

R/H

L/H

U

U/W

Latched

Dip

Main

Main

Switch

U/R

13

LOCK

UNLOCK

L/H

R/H

L/H

R/H

Actuators (LUCAS SYSTEM)

OR

OG

OG

OR

OW

NR

N

P

N

B

B

B

B

B

OU

+12v from
terminal post

Boot lock Motor Upgrade

Aditional wiring shown
within dotted line

The motorized actuator is
held at ground on both
sides while the relays lay at
rest. Once energised by ether
the lock or unlock triggers
(O/R or O/G) that
corresponding relay switches
one side to Positive and the
motor moves to lock or
unlock depending on the
systems request.

Radio - CD/Tape

Aerial

Delay relay unit

Boot Lights

BS

NP

Clock where fitted

In Line Fuse

WK

WK

OW

P

3

5

1

2

4

Jaguar XJ-S Boot Lock/Unlock and JaguarSport TWR Ariel Arrest

Hirschmann Style

85

86

87

87a

30/51

85

86

87

87a

30/51

85

86

87

87a

30/51

NP

Aerial Arrester Relay

Unlike the JaguarSport Arrester relay this one is wired after the delay relay so that
once the boot is opened far enough to activate the boot lights the aerial immediately starts
to descend even if the timer is still counting down. This way you preserve the delay stopping
the mast popping up and down as you move the key from Acc to Ignition.

Grounded through solinoid body

Thermail breaker

+12v Terminal Post

14

LH Window lift switch

LH Window motor

RH Window motor

R/G

GR

B

B

NU

NU

NU

N

WK

To Terminal post

To Ignition

Window Lift relay

Thermal Switch

85

86

87

87a

30/51

85

86

87

87a

30/51

1

2

3

6

7

8

LH Window motor

B

85

86

87

87a

30/51

1

2

3

6

7

8

N

To Terminal post

In line 2amp fuse

G/R

R/G

R/U

G/U

G/U

N

R/U

85

86

87

87a

30/51

Up

Rest

Down

Pins 1&3 -

Pins 2&6 +

Pins 1&3 +
Pins 2&6 +

Pins 1&3 +

Pins 2&6 -

Switch motion

and yes for some bizare reason

known only to the engineers at Lucas the motor
is live on both sides at rest.

1

2

3

6

7

8

1

2

3

6

7

8

1

2

3

6

7

8

Alternative relay operation circuit

This schematic involves swapping the Positive and Negative
terminals on the back of the switch.
This results in the relays and motors lying at negative when no
action is requested from the switch and should be given reasonable
consideration as the correct method.
Please insure that a copy of this circuit is inserted into your cars
literature and that you attach a label to the switch harness so that
the next owner or garage know that this car is non standard.
As to why Jaguar decided to wire this for constant positive! Its any
ones guess, one short and its game over.

Jaguar XJ-S Window Lift with 4 relay upgrade and Negitive rest

15

A

B

C

D

1

2

3

4

5

6

7

Park

Dela

y Unit

LG

OLG

ULG

RLG

WLG

BLG

A

Intermittent/

flick wipe

7-3-1 & 5-6

B

Fast Wipe

1-4 & 27

C

Slow Wipe

1-5 & 2-7

D

Off

1-7 and 5-6

85

86

87

87a

30/51

In line 35Afuse

Fuse 9

85

86

87

87a

30/51

85

86

87

30/51

85

86

87

87a

30/51

Wiper Motor

Run

Term
Post

This circuit was designed by Kirby Palm and is an adaptation from the one in his on-line book (see our links page).
Kirby rightly points out that this system provides a Solid Positive and Negative feed and is by far the best solution
which is why we substituted our original relay schematic for his superior one.
This is however not a direct copy, as we have re-configured the relays as an all in solution whereas his can be installed
as 1, 2 or 3 relays but we felt it is far better to go all the way. This is not a cure for wiper switch problems please see
the article in the support section of our web site at http://skjagtech.co.uk/html/support.htm for details.

Jaguar XJ-S Wiper under relay control

16