bonnet LAND ROVER DEFENDER 1999 Owner's Manual

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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 wire to the
ECU. If a fault occurs which involves incorrect mislock signals, alarm triggers and interior lamp operation, the door
switch earth may be the cause of incorrect operation.
If any door or the bonnet is opened, the switch closes and completes an earth path to the anti-theft alarm ECU.
This completed earth path input is sensed by the ECU, which, if armed, will sound the BBUS or alarm sounder.
The ECU also controls, via the door switches and ignition on/off signals, the operation of the interior lamps.
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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 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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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 battery voltage, keeping the LED extinguished.
When the system is armed and the bonnet and all doors are closed, the LED flashes quickly for a 10 second
confirmation period and confirms that perimetric and volumetric systems are armed. After the 10 second
confirmation period the LED flash changes to a slow flash to confirm that the alarm and immobiliser systems are
armed and to act as deterrent to thieves.
The LED also conveys CDL system information and this functionality is described in the Central Door Locking
(CDL) section.
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DESCRIPTION AND OPERATION CDL Using the Key
The driver and the passenger front doors are fitted with key barrel locks. Using the vehicle key in the passenger
door will only lock or unlock that door. Using the key in the drivers door will operate the CDL system and lock or
unlock all doors.
NOTE: The passenger door key barrel is connected to the door latch and has no electrical input to
the anti-theft alarm ECU. The driver door key barrel is also connected to the door latch and its
operation is monitored by the ECU only via the latch motor and the two wires connected to it.
When the vehicle is locked using the key in the drivers door, only CDL and perimetric protection is invoked.
Volumetric protection and active immobilisation is not initiated.
CDL Using the Remote Handset
The remote handset has two buttons; lock and unlock. A single press on the lock button will lock all doors and
invoke perimetric and volumetric protection and active immobilisation. Remote locking is inhibited if the
transponder coil senses that the key is in the ignition switch.
When the vehicle is locked, a single press of the unlock button will unlock all doors and disable perimetric and
volumetric protection. Immobilisation is only disabled using the transponder coil and the remote handset or the
EKA procedure.
Security LED
In addition to the alarm system status indications, the security LED also displays CDL system status.
The system confirms that the drivers door is open by illuminating the LED for the 10 second confirmation period. If
any other door or the bonnet is open, the LED remains unlit for the 10 second confirmation period. After the 10
second confirmation period the LED reverts to the slow flash deterrent mode if the alarm is armed.
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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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