sensor LAND ROVER DEFENDER 1999 Manual PDF

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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ELECTRICAL
17
DESCRIPTION AND OPERATION Interior Lamp Functionality
The anti-theft alarm ECU controls the interior lamp functionality. When the lamps are extinguished, they fade out
to the off condition over a 2 second period.
The lamps are turned on by:
Disarming the alarm using the remote handset
Opening any door.
When the lamps are on, they will be extinguished by the following actions:
If all doors are closed, the lamps will be extinguished after a 15 second delay period
If any door is left open, the lamps will be extinguished after an 8 minute delay period
If one of the above delay periods is active and the ignition is switched on or the alarm is armed, the lamps will
be extinguished.
ANTI-THEFT ALARM SYSTEM SELF TEST
The anti-theft alarm ECU has a self test feature which allows all alarm inputs to be tested. To enter self test mode
the following steps must be completed as follows:
1.Ensure that the driver’s door is closed and the driver’s window is open
2.Open the bonnet and with assistance depress and hold the bonnet switch
3.Release the bonnet switch and within 0.5 seconds turn the ignition switch on to position II
4.Quickly open the driver’s door
5.Turn the ignition switch to the off position
6.Turn the ignition switch back to position II
7.If the self test mode has been entered successfully, confirmation will be given by the alarm sounder. If the
ECU has not entered self test mode, repeat the above procedure.
Once in self test mode, the following test inputs will cause the security LED to illuminate and the engine
immobilised warning lamp and the hazard warning lamps to flash. When an input is operated, non illumination of
the security LED, the engine immobilised warning lamp and the hazard warning lamps indicates a fault for that
input.
Perform the following steps to test each input for correct operation:
Close and open the drivers door
Open and close each of the passenger doors and the tail door in turn
Close and open the bonnet (depress switch if bonnet still open)
With drivers door closed, lock and unlock the driver’s door using the vehicle key if spare key available. If spare
key is not available, operate driver’s sill button through open window
Press the unlock button of the remote handset. This enters the volumetric self test mode and all other inputs
will be disabled. Make a movement inside the vehicle. When the volumetric sensor is triggered the security
LED will flash.
To exit the self test mode, turn the ignition switch to the off position.
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