Land Rover Defender 1999 2002my Workshop Supplement Body Repair 2nd Edition Rover Manual

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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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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...

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DESCRIPTION AND OPERATION Door and Bonnet Switches
The bonnet switch is located at the rear of the bonnet aperture on the bulkhead. The door switches are located on
the’A’posts for the front doors, the’B’posts for the rear doors and on the inside face of the tail door aperture.
The drivers door switch and the bonnet switch are connected to the anti-theft alarm ECU on individual single
wires. The remaining passenger doors and, if applicable, the tail door are jointly connected on a single...

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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...

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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...

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DESCRIPTION AND OPERATION Alarm Sounders
1.Battery Backed Up Sounder (BBUS)
2.Alarm sounder
Two types of alarm sounder are available, dependant on the vehicle market configuration.
A Battery Backed-Up Sounder (BBUS) is used in some markets and located in the LH front wing, behind the
headlamp. This is a tamper proof sounder with its own power supply which allows it to continue operating even if
disconnected from the vehicle power supply. The BBUS is connected to a permanent battery supply...

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DESCRIPTION AND OPERATION Visual and Audible Warnings
Audible and visual warnings are dependant on market legislation. The hazard warning lamps are controlled by two
outputs from the anti-theft alarm ECU; one for the LH lamps and one for the RH lamps. To illuminate the warning
lamps the output from the ECU is at battery voltage. When the lamps are off, the output is driven to earth.
When the alarm is armed the hazard warning lamps will flash three times to indicate that the system is...

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DESCRIPTION AND OPERATION Security LED
The security LED has a number of functions to indicate anti-theft alarm system status. The LED is located in the
speedometer housing in the instrument pack. The LED receives a permanent battery supply via fusible link 6 in
the under seat fuse box. The LED is connected to the anti-theft alarm ECU which earths the connection when LED
operation is required. When the LED is not required to be illuminated, the anti-theft alarm ECU holds the
connection at...

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DESCRIPTION AND OPERATION Remote Handset
The remote handset is a separate unit from the vehicle key and is used to arm and disarm the alarm system. The
handset comprises two buttons; lock and unlock. The handset contains a battery (CR3032) and a printed circuit
board containing the circuitry to generate the RF signals.
NOTE: In selected markets, the vehicle key, when used in the drivers door key barrel switch, will
not disarm the alarm system.
The remote handset RF code consists of two...

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DESCRIPTION AND OPERATION This page is intentionally left blank