1999 LAND ROVER DEFENDER sensor

PANEL REPAIRS
3
REPAIR WHEEL ARCH - FRONT
Remove
The procedure to change the Inner Front Wheelarch is
the same as for the Wing Upper, except for removal of
the ABS sensors and shield, if fitted.
BULKHEAD ASSEMBLY
Remove
1.Disconnect both battery leads, negative lead
first.
2.Remove front lower wing.See this Section.
3.Remove RH and LH front upper wing.See this
Section.
4.Remove headlamp mounting panels.See this
Section.
5.Remove screen aperture.See this Section.
6.Remove both front doors.
7.Remove lower fascia panel.See CHASSIS
AND BODY, Repair.
8. Models with A/C:Remove relevant A/C pipes.
9.Remove front grille.
10.Drain cooling system.See COOLING
SYSTEM, Adjustment.
11.Remove radiator and intercooler.
12. Models with A/C:Remove condensor.
13.Remove air cleaner assembly.
14.Remove heater unit.See HEATING AND
VENTILATION, Repair.
15.Remove brake servo assembly.
16.Remove heater ducts.
17.Remove both front seats.
18.Remove front carpets.
19.Release all relevant harnesses and position
aside.
20.Remove facia support bracket.
Refit
21.Prepare and clean panel joint faces. Ensure all
necessary grommets and sealant is applied to
new bulkhead.
22.Reverse removal procedure.
23.Bleed brake system.See BRAKES,
Adjustment.
24.Align headlamps.See ELECTRICAL,
Adjustment.
25.Water test after refitting.
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AIR CONDITIONING
5
REPAIR
9.Disconnect multiplug from auxiliary relay
bracket.
10.Release drain pipe from evaporator.
11.Release evaporator from bulkhead grommet.
12.With assistance remove A/C duct assembly from
vehicle.
NOTE: Do not carry out further
dismantling if component is removed for
access only.
13.Disconnect blower motor multiplugs.
14.Remove 5 screws and remove blower unit from
A/C duct.
15.Disconnect multiplug from trinary switch.
16.Remove Allen screw, remove pipe assembly
from evaporator and discard’O’rings.
CAUTION: Immediately cap all air
conditioning pipes to prevent ingress of
dirt and moisture into the system.
17.Remove 7 screws and remove evaporator cover
from A/C duct.
18.Release temperature sensor and remove
evaporator.
19.Remove 2 Allen screws, remove TXV from
evaporator and discard’O’rings.
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82AIR CONDITIONING
6
REPAIR Refit
20.Clean TXV and mating face.
21.Lubricate new’O’rings with refrigerant oil and fit
’O’rings to pipes.
22.Position TXV and tighten Allen screws.
23.Position evaporator and fit sensor.
24.Position cover and tighten screws.
25.Clean pipes and mating faces.
26.Lubricate and fit new’O’rings, position pipes
and tighten Allen screw.
27.Connect trinary switch multiplug.
28.Position blower unit,tighten screws and connect
multiplugs.
29.With assistance position A/C duct assembly to
vehicle.
30.Connect drain pipe to evaporator.
31.Connect multiplug to relay bracket.
32.Align A/C duct to fascia, tighten securing bolt
and screws.
33.Position speakers and connect Lucars.
34.Position relay bracket and tighten bolts.
35.Clean pipes and mating face.
36.Lubricate and fit new’O’rings to evaporator
pipes.
37.Position pipes and tighten bolts to6Nm(4
lbf.ft).
38.Renew receiver drier.See this Section.
39.Recharge A/C system.See Adjustment.
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ELECTRICAL
1
DESCRIPTION AND OPERATION SECURITY AND CENTRAL DOOR LOCKING
SYSTEM - FROM 02MY
The following description details the functionality and operation of the 10AS Security and Central Door Locking
(CDL) System fitted to 2002MY Defender. The system contains some new features and also retains some
features from previous Defender models. The alarm system and CDL system are controlled by the 10AS anti-theft
alarm ECU.
New door lock barrels are introduced and use the same key as the ignition switch barrel, thereby eliminating the
requirement for a separate key for the doors.
NOTE: Some markets will only have some of the features described and some will have no
security or central door locking functions.
The security system comprises the following components:
10AS anti-theft alarm ECU
Remote handset transmitters
Transponder coil
Volumetric sensor
CDL actuators
Bonnet switch
Driver’s door key barrel switch
Door switches
Bonnet switch
Battery Backed-Up Sounder (BBUS) or alarm sounder
Security LED
Engine immobilised warning lamp
Direction indicators
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86ELECTRICAL
2
DESCRIPTION AND OPERATION SECURITY AND CENTRAL DOOR LOCKING
SYSTEM COMPONENTS - FROM 02MY
1.Engine immobilisation warning lamp
2.Security LED
3.Transponder coil
4.CDL actuators (tail door shown)
5.Immobilisation ECU (300Tdi models only)
6.Remote handset and key7.Door switches
8.Bonnet switch
9.Alarm sounder
10.Battery Backed Up Sounder (BBUS)
11.Anti-theft alarm ECU
12.Volumetric sensor
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ELECTRICAL
3
DESCRIPTION AND OPERATION ANTI-THEFT ALARM - FROM 02MY
The alarm and immobilisation system on 2002MY Defender is similar to that used on Discovery Series I (LJ)
models from 1996MY. The alarm system comprises the anti-theft alarm ECU, bonnet and door switches and a
volumetric sensor.
Anti-Theft Alarm ECU
The anti-theft alarm ECU is located behind the instrument pack and receives a permanent battery supply via fuses
6 and 7 in the under seat fuse box. The ECU also receives a battery supply via the ignition switch position II and
fuse 1 in the passenger compartment fuse box. The ECU is connected to the various supporting components by
two harness connectors.
The ECU controls the alarm system (perimetric and volumetric security), CDL system, engine immobilisation
system (Td5 only) and various other vehicle functions including direction indicators and interior lamps.
The anti-theft alarm ECU incorporates an RF receiver and antenna for reception of RF signals from the remote
handset for locking and alarm arming. The antenna is unterminated at one end, and for optimum performance the
antenna must not be wound around adjoining harnesses.
The anti-theft alarm ECU operates at one of two frequencies which are identified by a label on the unit. The
frequencies are:
433 MHz - Europe, Gulf States, South Africa
315 MHz - North America, South East Asia, Japan, Australia.
The anti-theft alarm ECU also incorporates an integral inertia switch. In the event of an impact of sufficient severity
to trigger the inertia switch when the ignition is on, the ECU will unlock all doors and operate the hazard warning
lamps. The ECU will remain in this condition for a pre-programmed period of 2 minutes. To reinstate CDL
functionality and to deactivate the hazard warning lamps, the ignition should be turned off and then on after the 2
minute timer has expired.
NOTE: There is a separate inertia switch for fuel cut off.
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ELECTRICAL
5
DESCRIPTION AND OPERATION Perimetric Protection
Perimetric protection is the monitoring of each opening door or bonnet to unauthorised intrusion. The anti-theft
alarm ECU uses the door and bonnet switches described previously to determine when illegal intrusion has
occurred.
If a door/bonnet is left open when the alarm system is armed, the ECU will determine a mislock situation which is
indicated by non operation of the hazard warning lamps. If the drivers door is left open, the security LED in the
instrument pack will be illuminated for the 10 second confirmation period. If any other door or the bonnet is left
open the security LED will remain off for the 10 second confirmation period. After the confirmation period, the LED
will revert to the 1Hz deterrent flash.
If the door/bonnetis subsequently closed, the hazard warning lamps will flash to show that full perimetric protection
is now invoked. The security LED will also resume the 10 second confirmation flash.
If only the bonnet is left open, all doors will have perimetric protection and volumetric protection will also be set. If
a door is left open, the volumetric protection is suspended until that door is subsequently closed.
Volumetric Protection
The vehicle alarm system can be armed with or without volumetric protection activated. If volumetric protection is
required, the vehicle must be locked using the lock button on the remote handset. If volumetric protection is not
required, because a pet is to be left in the vehicle for instance, the vehicle must be locked using the vehicle key in
the drivers door lock.
When the vehicle is locked using the remote handset, the volumetric sensor will wait for a period of 15 seconds
before arming. This allows time for the air in the vehicle to settle and prevent incorrect activation of the alarm.
If volumetric protection is set and there is a disturbance in the vehicle, i.e., a window left open or a moving object
in the vehicle, within the 15 second period, the volumetric sensor will not activate. The sensor must detect no
disturbance for the full 15 second period before arming.
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86ELECTRICAL
6
DESCRIPTION AND OPERATION Volumetric Sensor
The volumetric sensor is located behind the RH’B’post on 90/110 station wagon models, on the headlining
between the interior lamp and rear view mirror on 90/110 pick-up models and on the headlining above the RH
door on 130 crewcab models.
The volumetric sensor operates by emitting a signal, which is received back to the sensor as it bounces back from
objects inside the vehicle. Once armed, the sensor will detect a disturbance to the returned waves. This is sensed
by the anti-theft alarm ECU which activates the alarm sounder or BBUS.
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