1996 LAND ROVER DEFENDER open bonnet

10MAINTENANCE
2
MAINTENANCE BATTERY CONNECTIONS
NOTE: The vehicle may be fitted with an
alarm and immobilisation system using a
battery backed-up alarm sounder.
See
ELECTRICAL, Repair, Battery
Disconnect battery leads, clean and grease with
petroleum jelly, including battery terminals.
CHECK OPERATION OF DOOR SWITCHES
When a Vehicle Immobilisation and Alarm System is
fitted it is important that all door and bonnet switches
operate correctly, otherwise perimeter and interior
protection may not function if a door or the bonnet is
opened.VEHICLE EXTERIOR
CHECK/ADJUST HEADLAMP ALIGNMENT
Check/adjust headlamp alignment.
CHECK ROAD WHEELS AND TYRES
Check road wheels for damage.
Check tyres, including spare, for compliance with
manufacture's specificaton.
Check visually for cuts, lumps, bulges, uneven tread
wear and tread depth.
See INTRODUCTION,
Information, wheels and tyres
Check/adjust tyre pressures.See WHEELS AND
TYRES, Repair, Tyres pressures
INSPECT BRAKE PADS FOR WEAR, CALIPERS
FOR LEAKS AND CONDITION OF DISCS
Check thickness of brake pads, and renew if thickness
is less than 3,00 mm (0.12 in). Check brake pads for
oil contamination and fit a new set, if necessary,
See
BRAKES, Repair, front brake pads
orSee
BRAKES, Repair, rear brake pads
WARNING: When renewing brake pads, it
is essential that only genuine components
with correct grade of lining are used.
Always fit new pads as complete axle sets, NEVER
individually or as a single wheel set. Serious
consequences could result from out of balance
braking due to mixing of linings.
CHECK FRONT WHEEL ALIGNMENT
Use recognised wheel alignment equipment to carry
out this operation.
See STEERING, Adjustment,
front wheel alignment
CHECK OPERATION OF ALL DOORS/TAILGATE,
BONNET AND LOCKS
LUBRICATE ALL DOOR/TAILGATE HINGES, AND
DOOR CHECK/LOCK MECHANISMS

19FUEL SYSTEM
12
REPAIR HEATER PLUG CONTROL UNIT
Service repair no - 19.60.33
Remove
1.Disconnect battery.
2.Remove screw securing control unit to bulkhead.
3.Disconnect multi-plug and release control unit.
Refit
4.Fit harness multi-plug to control unit.
5.Secure control unit to bulkhead.
6.Reconnect battery.AIR CLEANER
Service repair no - 19.10.01
Remove
1.Slacken hose clip and detach outlet hose.
2.Release clips and open air cleaner retaining
straps.
3.Lift up air cleaner, slacken hose clip and detach
inlet hose.
4.Remove air cleaner.
Refit
5.Position air cleaner and connect inlet hose.
6.Close air cleaner retaining straps and secure
lock clips.
7.Connect outlet hose.
NOTE: If an EGR fuel system is fitted,
ensure the modulator valve vacuum spill
pipe is secure in the outlet hose.
AIR CLEANER ELEMENT
Service repair no - 19.10.10
For remove and refit procedure.
See SECTION 10,
Maintenance, Under bonnet maintenance

76CHASSIS AND BODY
32
REPAIR BONNET LOCK
Service repair no - 76.16.21
Remove
1.Open bonnet.
2.Mark position of guide plate and lock to bonnet
platform.
3.Remove 8 screws securing grille.
4.Remove grille.
5.Remove 2 bolts securing guide plate and lock.
6.Remove guide plate.
7.Release spring securing lock to bonnet platform.
8.Slacken clamping bolt securing bonnet release
cable.
9.Remove lock.
Refit
10.Fit spring between lock and bonnet platform.
11.Position lock and guide plate to bonnet platform
and nip up bolts.
12.Position guide plate and lock to position marks
and tighten bolts to
10 Nm (7 lbf/ft).
13.Fit cable to lock and tighten clamping bolt.
14.Check operation of release cable and adjust if
necessary.
15.Fit grille and tighten securing screws.
16.Close bonnet.BONNET RELEASE CABLE
Service repair no - 76.16.29
Remove
1.Open bonnet.
2.Remove 8 screws securing grille.
3.Remove grille.
4.Slacken clamping bolt securing bonnet release
cable.
5.Remove cable from lock.
6.Release cable from clip on underside of bonnet
platform.
7.Feed cable through valance and collect
grommet.
8.Release cable from clip fixed to wheelarch under
expansion tank.
9.Loosen clamping nut securing bonnet release
handle to mounting bracket.
10.Remove bonnet release handle from mounting
bracket.
11.Withdraw cable through bulkhead.
Refit
12.Feed cable through bulkhead and fit bonnet
release handle to mounting bracket. Tighten
clamping nut.
13.Route cable behind expansion tank and fit to
securing clip.
14.Feed cable through valance.
15.Fit grommet between cable and valance.
16.Fit cable to securing clip on underside of bonnet
platform.

AIR CONDITIONING
5
ADJUSTMENT AIR CONDITIONING SYSTEM - PERFORMANCE
TEST
WARNING: R134a is hazardousSee
Repair, General Precautions
Carry out this test with bonnet and doors or windows
open, air conditioning switched on, temperature
control set to cold and blower at maximum speed. Set
the air supply control to supply fresh air.
1.Close low pressure valve on refrigerant station.
2.Close high pressure valve on refrigerant station.
3.Connect a Refrigerant Station to the high and
low pressure servicing connections.4.Insert dry bulb thermometer into cold air outlet
and position dry and wet bulb thermometer close
to outside air inlet.
Do not spill water from the wet thermometer
(psychrometer).
5.Start engine and run it at 1500 rev/min for 10
minutes with air conditioning switched on.
6.Read both pressure gauges and thermometers.
Check readings against table below with
humidity between 60% and 80%.
7.Switch off air conditioning, stop engine,
disconnect test equipment.
Performance range
Intake temperature Outlet temperature Low pressure High pressure
20 - 24°C4-10°C 18 - 28 lbf/in
2213 - 299 lbf/in2
1.2 - 1.9 bar 14.7 - 20.6 bar
25 - 29°C9-19°C 27 - 37 lbf/in2256 - 341 lbf/in2
1.9 - 2.6 bar 17.6 - 23.5 bar
30 - 35°C20-27°C 33 - 47 lbf/in2299 - 384 lbf/in2
2.3 - 3.2 bar 20.6 - 26.5 bar
Table 1
Ambient Compound Gauge High Pressure
Temperature Readings Gauge Readings
°C°F bar lbf/in
2bar lbf/in2
16 60 1,03-1,4 15-20 6,9-10,3 100-150
26,7 80 1,4-1,72 20-25 9,6-13,1 140-190
38 100 1,72-2,1 25-30 12,4-15,5 180-225
43,5 110 2,1-2,4 30-35 14,8-17,2 215-250

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.

ELECTRICAL
5
DESCRIPTION AND OPERATION REV: 05/99 ALARM SYSTEM OPERATION
Arming alarm
To arm the alarm, aim handset at vehicle and press
the RH button (Padlock symbol). Provided all doors
and or apertures are closed, the direction indicator
lamps will flash three times to confirm that the alarm is
armed. All security features previously described will
be active.
Once armed, the alarm will sound if a door or the
bonnet is opened, or if movement is detected inside
the vehicle.
Disarming alarm
Within range of the vehicle, briefly press the LH
(Plain) button on the handset; the direction indicator
lamps will flash once to indicate that the alarm has
been disarmed and the engine re-mobilised.
NOTE: In some territories, the interior
lamps will illuminate when the alarm is
disarmed.
If the direction indicators fail to flash when the
alarm is armed:
This indicates that a door or the bonnet is not fully
closed, in which case the alarm will be partially armed
and engine immobilised, but interior protection will not
be active.
Once the open door or bonnet is closed, the direction
indicators will flash three times and the alarm will fully
arm as described previously.
If the alarm sounds:
The vehicle horn and alarm sounder will operate
continuously for 30 seconds when the alarm is
triggered. The horn and alarm sounder can be
triggered up to three times.
To silence the alarm, press either handset button. If
the handset is inoperative, the alarm can only be
disarmed by entering the emergency key access
code, seeEngine immobilisation override.Anti-theft alarm indicator light
A RED indicator light on the instrument panel
indicates the status of the alarm system. When the
alarm is armed successfully, the light flashes rapidly.
After 10 seconds, the light adjusts to a slower
frequency and continues flashing as an anti-theft
deterrent.
If the light fails to illuminate during the rapid flash
phase, this indicates a 'mislock' (door or the bonnet
not fully closed or key in starter switch). If this occurs,
the indicator light will still flash at slower frequency as
an anti-theft deterrent.
The indicator light will illuminate continuously under
the following conditions:
1.Alarm system armed and immobilised with
ignition 'on' or driver's door open.
2.Engine immobilised with ignition 'on' or driver's
door open.
Interior protection
Interior protection is activated automatically when the
alarm system is armed; twin sensors inside the
vehicle monitor interior space and will activate the
alarm if an intrusion is detected.
However, if passengers or animals are to be left inside
the vehicle, or if a window or sunroof is to be left
open, the alarm must be armed with the interior
protection DISABLED as follows:
To disable interior protection:
1.Open the driver's door.
2.Use the handset to arm the alarm in normal way.
3.Close the driver's door (the direction indicator
lamps will flash three times and the anti-theft
indicator light commences flashing rapidly). The
alarm system is now armed with the interior
protection disabled.
NOTE: Interior protection will not operate
until 15 seconds after the alarm is set.

86ELECTRICAL
12
DESCRIPTION AND OPERATION VEHICLE ALARM SYSTEM BUILT-IN TEST
NOTE: The handset should be detached
from the key to allow perimetric testing of
the alarm system. The system will
automatically switch to volumetric testing if the
handset is in close proximity to the starter switch.
The built-in test procedure can be accessed providing
the following conditions exist:
Alarm disarmed.
Ignition 'off'.
Doors unlocked.
Bonnet closed.
With assistance, the test mode can be entered by
completing the following instructions within 5 seconds:
1.Open bonnet.
2.Turn starter switch 'on'.
3.Open driver's door (far enough to activate door
switch).
4.Turn starter switch 'off'.
5.Turn starter switch 'on'.
If the test mode has been correctly accessed, the
alarm sounder/horn will operate briefly and the
anti-theft alarm indicator and direction indicator lamps
will flash.
Perimetric tests
The anti-theft alarm indicator light and direction
indicator lamps will flash when:
1.Door switches are activated.
2.The bonnet is opened.
3.Key switches are activated.Volumetric tests
Press the LH (unlock) button or move the handset
close to the starter switch to disable perimetric testing
and enable volumetric testing. If movement is
detected within the vehicle by the ultrasonic sensor
the anti-theft alarm indicator and direction indicator
lamps will illuminate.
NOTE: Exit the anti-theft alarm built-in test
by turning the starter switch to the 'off'
position.
If the previously described conditions are not achieved
during the built-in test procedure, this would indicate a
fault in the alarm system. Before undertaking detailed
fault diagnosis procedures, first make visual checks of
components such as a faulty door switch or blown
alarm system fuse.