1996 LAND ROVER DEFENDER ECU

WIPERS AND WASHERS
7
REPAIR Refit
NOTE: During reassembly all fixings
related to wiper motor and wheelboxes are
finger tightened only, until all components
are correctly aligned.
12.Fit wheelboxes to bulkhead and secure with
retaining nuts and washers.
13.Fit drive rack tubes to wheelboxes.
14.Apply grease to drive rack and wheelboxes.
15.Align wiper motor and mounting pad, secure with
retaining strap and tighten drive tube nut.
16.Fully tighten wheelbox back plate nuts.
17.Fully tighten both wheelbox spindle nuts.
18.Fit wiper arm adaptors and secure with grub
screw.
19.Before refitting panels fit wiper blades, connect
multi-plug and earth lead, reconnect battery and
check wiper operation.
20.If satisfactory, secure steering column upper and
lower fixings and tighten to correct torque.
21.Fit ventilator grille panel, fascia crash pad,
instrument housing and all other components
removed to gain access to wiper motor and
wheelboxes.

84WIPERS AND WASHERS
8
REPAIR WINDSCREEN WIPER WHEELBOXES - AIR
CONDITIONED VEHICLES
Service repair no - 84.15.25/20
Remove
1.Disconnect battery.
2.Remove wiper motor and drive rack
See Wiper
motor and drive rack - air conditioned
vehicles.
3.Remove centre and LH fascia top crash rail
support bracket fixings.
4.Remove both demister vents from ducts.
5.Remove RH demister vent hose from duct.
6.Remove RH vent demister vent fixing and pivot
vent and hose aside.
7.Remove demister vent top duct.8.Release steering column upper and lower
support rods.
9.Slacken LH and RH wheelbox nuts and remove
drive tubes from wheelboxes.
10.Remove wiper arm splined adaptor.
11.Remove spacer, where fitted, early vehicles
only.
12.Remove nuts securing left and RH wheel boxes
and withdraw wheelboxes from bulkhead.
NOTE: During assembly all fixings related
to wiper motor and wheelboxes are finger
tightened only until all components are
correctly aligned.

WIPERS AND WASHERS
9
REPAIR 13.Fit wheelboxes to bulkhead.
14.Fit drive tubes to wheelboxes.
15.Feed drive rack through tubes until fully seated
in both wheelboxes.
16.Secure drive tube nut to wiper motor.
17.Fit wiper motor strap and earth lead.
18.When all components are correctly aligned, fully
tighten wheelboxes nuts to secure drive tubes.
Tighten wheelbox to bulkhead nuts.
19.Fully tighten drive tube nut to wiper motor and
motor strap screws.
20.Connect multiplug to wiper motor and earth lead
to strap tag.
21.Fit spacer, where used, early vehicles only.
22.Fit wiper arm adaptors.
23.Reconnect battery and check operation of wiper
motor and drive assembly and wheelboxes.
24.Disconnect battery.
25.Fit steering column upper and lower supports.
Tighten fixings to correct torque.
26.Fit demister vent top duct.
27.Secure RH demister vent and hose.
28.Fit LH and RH demister vents to ducts.
29.Fit centre and LH fascia top crash rail support
brackets.
30.Fit all other components removed to gain access
to wiper motor and wheelboxes.
31.Reconnect battery, check wiper motor operation
again and adjust wiper arms, if necessary.REAR WIPER MOTOR
Service repair no - 84.35.12
Remove
1.With assistance, unscrew 3 retaining nuts and
remove spare wheel from rear door mounting
studs.
2.Lift wiper arm end cap to gain access to securing
nut.
3.Remove nut and withdraw wiper arm from drive
spindle.
4.Remove retaining nut, plain washer and rubber
washer securing wiper motor drive spindle to
door.
5.Remove 2 screws and remove cover from wiper
motor mounting bracket.
6.Disconnect wiper motor harness multi-plug.
7.Remove bolt, with rubber washer, and detach
wiper motor, complete with mounting bracket,
from rear door.

84WIPERS AND WASHERS
10
REPAIR Refit
8.Locate wiper motor drive spindle through
aperture in rear door.
9.Position wiper motor mounting bracket and
secure to rear door. Tighten bolt to
23 Nm (17
lbf/ft).
10.Reconnect harness multi-plug.
11.Secure drive spindle to door.
12.Fit wiper motor cover.
13.Fit rear wiper arm.
14.Fit spare wheel. Tighten retaining nuts to
130Nm
(96 lbf/ft).

WIPERS AND WASHERS
1
OVERHAUL WIPER MOTOR
Service repair no - 84.15.18.
Dismantle
1.Remove wiper motor from vehicle
See Repair,
Wiper motor and drive rack.
2.Remove wiper motor gearbox cover.
3.Remove circlip and plain washer securing
connecting rod.
4.Withdraw connecting rod.
5.Withdraw flat washer.
6.Remove circlip and washer securing shaft and
gear.
7.Clean any burrs from gear shaft and withdraw
gear.
8.Withdraw dished washer.
9.Add alignment marks to yoke and gearbox for
reassembly.
10.Remove yoke securing bolts.11.Withdraw yoke and armature.
12.Remove brush gear assembly.
13.Remove limit switch.
Inspection and test
14.Check brushes for excessive wear, if they are
worn to 4,8 mm in length, fit a new brush gear
assembly.
15.Using a push type gauge, check that brush
spring pressure is 140 to 200 g when bottom of
brush is level with bottom of slot in brush box. Fit
a new brush gear assembly if springs are not
satisfactory.
16.Test armature for insulation and open- or
short-circuits. Use a 110 V 15 W test lamp. Fit a
new armature if faulty.
17.Examine gear wheel for damage or excessive
wear.
Key to wiper motor components
1.Flexible drive
2.Gearbox cover
3.Connecting-rod retaining washer and circlip
4.Connecting-rod
5.Flat washer
6.Gear shaft retaining washer and circlip
7.Drive gear8.Dished washer
9.Alignment marks - yoke to body
10.Yoke securing bolts
11.Armature and yoke
12.Brush gear assembly
13.Limit switch

84WIPERS AND WASHERS
2
OVERHAUL Assemble
Use Ragosine Listate Grease to lubricate gear wheel
teeth, armature shaft worm gear, connecting rod and
pin, cable rack and wheelbox gear wheels.
Use Shell Turbo 41 oil sparingly to lubricate bearing
bushes, armature shaft bearing journals, gear wheel
shaft and wheelbox spindles. Thoroughly soak felt
washer in yoke bearing with oil.
18.Fit limit switch.
19.Fit brush gear assembly.
20.Fit armature and yoke to gearbox using
alignment marks, secure with yoke retaining
bolts tightening to
23 Nm (17 lbf/ft).If a
replacement armature is being fitted slacken
thrust screw to provide end-float for fitting yoke.
21.Fit dished washer beneath gear wheel with
concave side towards gear wheel.
22.Fit gear wheel to gearbox.
23.Secure gear wheel shaft with plain washer and
circlip.
24.Fit larger flat washer over crankpin.
25.Fit connecting rod and secure with smaller plain
washer and circlip.
26.Fit gearbox cover and secure with retaining
screws.
27.Connect electrical leads between wiper motor
and limit switch.
28.To adjust armature shaft end-float, hold yoke
vertically with adjuster screw uppermost.
Carefully screw in adjuster until resistance is felt,
then back-off one quarter turn.

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.