1996 LAND ROVER DEFENDER fuel

70BRAKES
18
REPAIR VACUUM PUMP
Service repair no - 70.50.19
Remove
NOTE: To ease pump removal set engine
to T.D.C. on No.1 cylinder.
1.Disconnect battery.
2.Remove air cleaner
See FUEL SYSTEM,
Repair, Air cleaner
.
3.Detach servo hose from vacuum pump.
4.Remove bolt securing air cleaner support
bracket strut.
5.Remove 6 bolts securing vacuum pump.
6.Detach pump complete with strut and harness
bracket. Note location of strut and bracket for
Refit.
Refit
7.Clean mating faces of pump and block.
8.Loosely assemble pump to block with a new
gasket and with air cleaner strut and harness
bracket located under heads of bolts noted
during Remove.
9.Evenly tighten bolts, to depress pump plunger,
finally tightening to
25 Nm (18 lbf/ft).
10.Secure strut to air cleaner bracket.
11.Connect vacuum hose and secure with clip.
12.Refit air cleaner
See FUEL SYSTEM, Repair,
Air cleaner
.

86ELECTRICAL
2
DESCRIPTION AND OPERATION VEHICLE IMMOBILISATION AND ALARM SYSTEM
A sophisticated engine immobilisation and anti-theft
alarm system is offered on the Land Rover Defender
300 Tdi vehicle range, which incorporates the
following features:
Perimeter protection
This part of the alarm system protects side doors,
bonnet and rear door against unauthorised entry -
alarm sounding if any one of these apertures is
opened without alarm first being disarmed.
Interior protection
Also known as volumetric protection, this part of the
system protects space inside the vehicle. Once
armed, the alarm will sound if a door is opened, or if
movement is detected inside the vehicle.
Engine immobilisation
The engine is immobilised electronically whenever the
alarm system is armed. Even if the alarm has not
been armed, engine immobilisation will occur
automatically thirty seconds after the driver's door is
opened, or five minutes after the starter switch is
turned to position '0'.
ALARM SYSTEM COMPONENTS
Electronic control unit (ECU)
The ECU is the alarm system brain and controls all
vehicle immobilisation and alarm functions. It
responds to the inputs received, by supplying suitable
outputs to indicate status of the alarm system or
activating relevant warning devices. unit is located
under fascia behind instrument binnacle.
Handset and key
The handset is the primary source of control for the
alarm system i.e. it arms and disarms the alarm
components. The key can be used to override engine
immoblisation if the handset is lost or fails to operate,
seeEngine immobilisation override.The handset battery should last for approximately
three years dependent upon use. The following
symptoms will be noticed when the battery requires
replacement:
1.The handset will only work every other operation
while disarming.
2.The direction indicator lamps will not flash when
the alarm is disarmed.
For battery replacement procedure, seeHandset
Battery.
Passive coil
The passive coil is fitted on the starter switch and
activates a receiving coil in the handset, causing it to
automatically transmit a remobilisation signal to the
ECU.
Aerial
The aerial is integral within the alarm system harness
and supplies the ECU with the signal received from
handset.
Immobilisation spider
The immobilisation spider provides an interface
between ECU and immobilised areas of the vehicle.
This is installed in a sealed (safe) box inside the
vehicle battery box.
Digital diesel shut-off valve - 97 MY
When fitted, the digital diesel shut-off valve
immobilises the fuel injection pump by preventing
power reaching the fuel shut-off solenoid,
See
Immobilisation and alarm system circuit diagram -
with DDS
.

ELECTRICAL
3
DESCRIPTION AND OPERATION Door and bonnet switches
Perimetric protection for the vehicle is provided by
ECU inputs connected to the starter switch, bonnet
switch and door switches.
Ultrasonic sensor
The ultrasonic sensor operates by emitting an air
pressure carrier wave which is subsequently received
by the sensor as it bounces back from objects inside
the vehicle. Once armed, the alarm will sound if wave
is disturbed by a door opening, or if movement is
detected inside the vehicle.
When the volumetric sensor is activated it monitors
movement within the vehicle for 15 seconds before
detecting and responding to intrusions. If the sensor
detects movement it delays arming until a quiet period
has lapsed; if continuous movement is detected, the
alarm will not arm volumetrically.
NOTE: Interior protection will not operate
until 15 seconds after alarm is set.
The ultrasonic sensor is positioned in a different
location, according to vehicle type, as follows:
·90/110 Station Wagon - RH cantrail trim
·90/110 Pick-up - On headlining, between interior
lamp and rear view mirror
·130 Crewcab - On headlining above RH door
Alarm sounder
Two types of alarm sounder can be fitted, one with a
battery back-up facility and or without battery back-up,
both providing an audible warning whenever the alarm
is triggered. The vehicle horn will also operate if the
alarm sounds.
The alarm sounder is fitted to LH inner front wing in
the engine compartment.
NOTE: Disconnecting the battery on
vehicles fitted with the battery backed-up
facility will result in the alarm sounding, if
correct procedure has not been followed.Engine immobilisation warning light
The engine immobilisation warning light is located on
the instrument panel, and provides a visual indication
that the engine is immobilised.
Anti-theft alarm indicator light
The anti-theft alarm indicator light is located on the
instrument panel, between the fuel and coolant
temperature indicators, and provides a visual
indication of the alarm/ immobiliser status.

86ELECTRICAL
4
DESCRIPTION AND OPERATION REV: 05/99 ALARM SYSTEM COMPONENT LOCATION
COMPONENT LOCATION
1. Electronic control unit (ECU) Under dash, LH and RH drive
2. Anti-theft alarm indicator light Instrument panel
3. Engine immobilisation warning light Instrument panel
4. Immobilisation spider* Inside vehicle battery box
5. Passive coil Over starter switch barrel
6. Bonnet switch Engine compartment, LH and RH drive
7. Door switches
8. Ultrasonic sensor Varies according to vehicle type
9. Handset and key
10. Alarm sounder (without battery back-up) LH inner front wing
11. Alarm sounder (with battery back-up) LH inner front wing
* Replaced in some markets by a digital diesel shut-off valve (DDS), secured directly to fuel shut-off solenoid on
injection pump.

ELECTRICAL
9
DESCRIPTION AND OPERATION IMMOBILISATION AND ALARM SYSTEM CIRCUIT
DIAGRAM
1.Anti-theft alarm indicator light (LED)
2.Engine immobilisation warning light
3.Alarm system fuse - 15 amp
4.Alarm sounder relay
5.Under bonnet lighting fuse
6.Alarm sounder (without battery back-up)
7.Alarm system fuse - 5 amp (position 20)
8.Electronic control unit (ECU)
9.Bonnet switch
10.Alarm sounder protection fuse - 20 amp
(position 10)
11.Starter switch
12.Under bonnet ignition fuse
13.Driver's door switch
14.Vehicle horn switch
15.Vehicle horn
16.Passive coil
17.Starter switch relay
18.Front passenger door switch
19.Hazard warning light fuse - 15 amp (position 1)
20.Ultrasonic sensor
21.Interior lamp and horn fuse - 20 amp (position 3)
22.Alarm sounder (with battery back-up)
23.LH direction indicator lamps
24.RH direction indicator lamps
25.Interior lamp
26.Immobilisation spider
27.Rear side doors and rear door switches
28.Diagnostic connector
29.Diagnostic fuse - 7.5 amp
30.Starter solenoid
31.Fuel switch-off solenoid (injection pump)
32.Generator
33.AerialKey to cable colours
B-Black
G-Green
K-Pink
LG-Light Green
N-Brown
O-Orange
P-Purple
R-Red
S-Slate
U-Blue
W-White
Y-Yellow
The last letter of a colour code denotes the tracer
colour

ELECTRICAL
11
DESCRIPTION AND OPERATION IMMOBILISATION AND ALARM SYSTEM CIRCUIT
DIAGRAM - WITH DDS
1.Anti-theft alarm indicator light (LED)
2.Engine immobilisation warning light
3.Alarm system fuse - 15 amp
4.Alarm sounder relay
5.Under bonnet lighting fuse
6.Alarm sounder (without battery back-up)
7.Alarm system fuse - 5 amp (position 20)
8.Electronic control unit (ECU)
9.Bonnet switch
10.Alarm sounder protection fuse - 20 amp
(position 10)
11.Starter switch
12.Under bonnet ignition fuse
13.Driver's door switch
14.Vehicle horn switch
15.Vehicle horn
16.Passive coil
17.Starter switch relay
18.Front passenger door switch
19.Hazard warning light fuse - 15 amp (position 1)
20.Ultrasonic sensor
21.Interior lamp and horn fuse - 20 amp (position 3)
22.Alarm sounder (with battery back-up)
23.LH direction indicator lamps
24.RH direction indicator lamps
25.Interior lamp
26.Digital diesel shut-off valve (DDS)
27.Rear side doors and rear door switches
28.Diagnostic connector
29.Diagnostic fuse - 7.5 amp
30.Starter solenoid
31.Fuel shut-off solenoid (injection pump)
32.Generator
33.AerialKey to cable colours
B-Black
G-Green
K-Pink
LG-Light Green
N-Brown
O-Orange
P-Purple
R-Red
S-Slate
U-Blue
W-White
Y-Yellow
The last letter of a colour code denotes the tracer
colour

ELECTRICAL
19
REPAIR INSTRUMENT ILLUMINATION - BULB RENEWAL
Service repair no - 86.45.49 - Speedometer
Service repair no - 86.45.51 - Temperature gauge
Service repair no - 86.45.52 - Fuel gauge
Remove
1.Disconnect battery.
2.Remove 4 screws retaining instrument panel.
3.Ease panel forward and disconnect
speedometer cable to improve access to
illumination bulbs.
4.Twist bulb holder and pull from socket.
5.Pull bulb from holder.
Refit
6.Fit new bulb and refit holder.
7.Reconnect speedometer cable and fit instrument
panel.
8.Reconnect battery.STARTER SWITCH
Service repair no - 86.65.03
Remove
1.Remove instrument panel
See INSTRUMENTS,
Repair, Instrument panel.
2.Remove steering column nacelleSee
STEERING, Repair, Steering column nacelle.
3.Note position of harness leads on back of starter
switch and disconnect lukars. If fitted, remove
alarm system passive coil from switch
See
Passive coil.
4.Remove single screw and withdraw starter
switch from steering column lock.
Refit
5.Fit new switch in steering column lock.
6.Connect harness leads to starter switch.
7.If applicable, fit alarm system passive coil
See
Passive coil.
8.Fit steering column nacelleSee STEERING,
Repair, Steering column nacelle.
9.Fit instrument panelSee INSTRUMENTS,
Repair, Instrument panel.

ELECTRICAL
25
REPAIR DIGITAL DIESEL SHUT-OFF VALVE (DDS)
Service repair no - 86.77.00
Remove
1.Remove fuel injection pump
See FUEL
SYSTEM, Repair, Fuel injection pump.
2.Drill out 2 shear bolts securing DDS valve and
clamp, using a 3.2 mm drill, to a depth of
approximately 5 mm.
CAUTION: Use a drill bushing to guide the
drill.
3.Using an extractor, remove the 2 DDS valve
retaining bolts and discard.
4.Release DDS valve from fuel shut-off solenoid.
5.Remove protective cap from shut-off solenoid.
6.Unscrew terminal nut, release terminal lead
eyelet and remove DDS valve.7.Remove protective cap retainer and release
DDS valve clamp from behind fuel shut-off
solenoid.
Refit
8.Position DDS valve clamp behind fuel shut-off
solenoid and fit protective cap retainer.
9.Fit DDS terminal lead to fuel shut-off solenoid.
Tighten nut to
2 Nm (1.5 lbf/ft).
10.Fit protective cap to fuel shut-off solenoid,
ensuring terminal lead is correcly routed on RH
side of cap.
11.Secure DDS valve to fuel cut-off solenoid and
clamp. Tighten new shear bolts progressively
until heads shear.
12.Fit fuel injection pump
See FUEL SYSTEM,
Repair, Fuel injection pump.