1999 LAND ROVER DEFENDER ignition

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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 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 via fuse 7 in
the under seat fuse box. Two further connections are made to the anti-theft alarm ECU and a fourth connection is
to an earth header. If the BBUS is disconnected without first being disarmed by the anti-theft alarm ECU, it will
operate for 4.5 minutes.
To disarm the BBUS, when the battery is to be disconnected for instance, the ignition must be turned on to
position II and back to the off position , after which a 17 second delay is initiated to allow the battery or BBUS
connector to be disconnected. If the BBUS sounds, it can be disarmed by unlocking the vehicle with the remote
handset.
Where a BBUS is not specified, a standard vehicle horn is used for the alarm sounder and is located in the LH
front wing, behind the headlamp. The sounder is operated by an alarm relay which is controlled by the anti-theft
alarm ECU. The relay receives a permanent battery supply via fusible link 6 in the under seat fuse box. The relay
coil is connected to the anti-theft alarm ECU which provides an earth for the coil when horn operation is required.
This operates the relay contacts and supplies battery voltage to the sounder, causing it to operate.
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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 parts. One part is a fixed code that is unique to the handset and the
second part is a rolling code which changes in accordance with a predetermined pattern. The anti-theft alarm ECU
can store the codes of up to four different remote handsets at any one time.
If the remote handset battery falls below a predetermined level, the handset will transmit an additional RF signal
code to the anti-theft alarm ECU when either button is depressed. The security LED will display this as two rapid
flashes every 0.5 seconds to visually display the low handset battery condition. This will continue for the 10
second confirmation period or until the ignition is switched on.
Resynchronisation of Remote Handset
If either the remote handset battery or the vehicle battery is removed or disconnected, the rolling part the handset
code is lost and the handset(s) need to be resynchronised to the anti-theft alarm ECU. The resynchronisation
procedure is as follows:
Disconnect the vehicle battery.
Wait for 30 seconds for residual current to dissipate.
Reconnect the vehicle battery.
Carefully prise the remote handset apart and remove the battery. Avoid unnecessary handling of the battery.
With the battery removed, press either the lock or unlock button several times to remove residual current from
the circuitry.
Check the handset battery with a voltmeter. If the battery voltage is less than 2.7 volts, replace the battery.
Ensure that the battery contact surfaces are clean and replace the battery in the handset clip with the + symbol
uppermost. Put the two halves of the handset case back together.
DO NOT press any buttons.
With the handset within range of the vehicle, press the lock button four times in quick succession. The
anti-theft alarm ECU will respond by locking the vehicle.
Press the unlock button once to complete the resynchronisation procedure.
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DESCRIPTION AND OPERATION IMMOBILISATION SYSTEM - FROM 02MY
Engine immobilisation is available on all 2002MY engine derivatives, although it is not available in selected
markets. On Td5 models, the immobilisation system is controlled directly by the anti-theft alarm ECU. On 300Tdi
models, the immobilisation system is controlled by an engine immobilisation ECU in conjunction with the anti-theft
alarm ECU.
When immobilisation occurs on Td5 models, engine crank is disabled by the anti-theft alarm ECU breaking the
earth path for the starter relay coil and the ECM disables the fuel pump relay and the glow plug relay.
When immobilisation occurs on 300Tdi models, engine crank is disabled by the anti-theft alarm ECU breaking the
earth path for the starter relay coil and the engine immobilisation ECU disables the fuel cut-off solenoid, the starter
motor solenoid and the glow plug relay.
Two types of immobilisation are available; passive and active.
Engine Immobilised Warning Lamp
The engine immobilised warning lamp is located in the instrument pack. The lamp is used by the anti-theft alarm
ECU to show that the engine is immobilised during an attempted engine start.
The warning lamp receives a battery supply from the ignition switch position I (aux) via the passenger
compartment fusebox. The anti-theft alarm ECU controls the warning lamp. When the warning lamp is not
required, the ECU supplies a battery supply to the warning lamp. When warning lamp operation is required, the
ECU provides an earth for the bulb.
If the ignition switch is moved to the crank position, but operation of the starter motor is prohibited and the engine
immobilised warning lamp flashes, then the anti-theft alarm ECU has not received the correct code from the
remote handset and the vehicle will remain immobilised. Ensure that the remote handset is in the proximity of the
transponder coil. If the remote handset is not available or inoperative, the immobilisation system can be disarmed
using the EKA procedure outlined later in this section.
If the ignition switch is turned to the crank position III and the remote handset is not in the proximity of the
transponder coil, engine immobilisation will remain active and the warning lamp will flash to inform the driver.
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DESCRIPTION AND OPERATION Passive Immobilisation
Passive immobilisation occurs when the key is removed from the ignition switch and the drivers door is opened,
after a period of 30 seconds the engine will become immobilised. If the ignition is turned off or the key is removed
from the ignition switch and drivers door is not opened, the engine will become immobilised after 5 minutes.
The passive immobilisation system operates in conjunction with the transponder coil located around the ignition
switch barrel. The transponder coil emits an electro magnetic waveform signal which excites the remote handset
into transmitting a remobilisation signal. When remobilisation is requested, the anti-theft alarm ECU transmits an
appropriate code to the ECM on Td5 models or the engine immobilisation ECU on 300Tdi models.
Active immobilisation
Active immobilisation is only invoked when the vehicle is locked using the remote handset. Active immobilisation
performs the same engine disable functionality as the passive immobilisation previously described, but includes
full CDL and activation of perimetric and volumetric alarm modes.
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DESCRIPTION AND OPERATION Emergency Key Access (EKA)
If the vehicle is in an immobilised condition and the remote handset is not available or inoperable, an EKA
procedure using the vehicle key is available to remobilise the engine systems. The EKA code is supplied with the
vehicle and is shown on the security card supplied with the owners handbook.
NOTE: This feature is only available in markets where full alarm functionality is specified.
The EKA code involves the input of a unique four digit code which is entered using the ignition switch and the
drivers door switch. Note that the alarm sounder will operate as soon as the drivers door is opened and will
continue until the sequence is successfully completed.
To enter the code (2, 3, 4, 5 for example) perform the following steps:
1.Remove the handset from the key ring and position the handset well away from the ignition switch when
entering the code.
2.Open the driver’s door and immediately insert the key in the ignition switch and turn the ignition switch to
position II. Hold this position until the alarm sounds, then switch the ignition off (position 0) and close the
driver’s door.
3.Enter the first digit of the code. Turn the ignition on (to position II) and then off twice. Open and close the
driver’s door to enter the first digit.
4.Enter the second digit. Turn the ignition on and then off, three times. Open and close the driver’s door to
enter the second digit.
5.Enter the third digit. Turn the ignition on and then off, four times. Open and close the driver’s door to enter
the third digit.
6.Enter the fourth digit. Turn the ignition on and then off, five times. Open and close the driver’s door to enter
the fourth digit. If the code has been entered correctly, the alarm LED in the instrument pack will extinguish
and the engine can be started after the last closure of the driver’s door.
If a digit is incorrectly entered, holding the ignition switch in the on position for more than 5 seconds will reset the
sequence. The code must then be re-entered from the beginning.
If the EKA code is correctly entered, the security LED will illuminate for 1 second, the immobilisation will be
disabled and the alarm sounder will cease to operate.
If the EKA code is incorrectly entered, the alarm sounder will sound twice and the correct code must be
re-entered, If the EKA code is incorrectly entered three times the system invokes a 30 minute lockout. This is
signalled by the LED flashing with a long illuminated period followed by a short extinguished period for the lockout
duration.
NOTE: Disabling the alarm and immobilisation system using the EKA procedure is only valid for
one ignition on/off cycle. When the ignition is switched off, the immobilisation system will be
activated after a period of 30 seconds. If the remote handset is still unavailable, the EKA
procedure will have to be repeated each time the vehicle is to be driven.
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DESCRIPTION AND OPERATION CENTRAL DOOR LOCKING (CDL) - FROM 02MY
The Central Door Locking (CDL) system is a new feature for 2002MY Defender.
NOTE: CDL operates all doors on Station Wagon and County Station Wagons. On all other
Defender 2002MY variants, CDL operates on the driver and front and rear passenger doors only.
General
CDL operates on all doors, including the tail door and is operated by pressing the appropriate button on the
remote handset, using the vehicle key in the drivers door lock or using the drivers door sill button.
The CDL system introduces electrically operated door latches which are controlled by the anti-theft alarm ECU,
located behind the instrument pack. The anti-theft ECU receives a permanent power supply from fuse 6 in the
passenger compartment fuse box. Each CDL latch motor is connected by two wires to the anti-theft ECU which
alternately supplies power and earth connections to drive each motor to the lock or unlock positions.
If the latch motors are continually operated in a short period of time, the anti-theft ECU will suspend all CDL latch
motor operation for 15 seconds to prevent the motors from overheating. Before suspension occurs the anti-theft
ECU ensures that all the doors are left in the unlocked condition.
If the vehicle is locked, and the key is in the ignition switch or the ignition is on and the anti-theft alarm ECU inertia
switch is tripped, all doors will be unlocked immediately and the hazard warning lamps will operate. To prevent
accidental relocking, all latch motors will be inhibited until the anti-theft ECU senses that the drivers door is
opened with the key removed from the ignition switch.
Locking of the vehicle using the remote handset is inhibited with the key in the ignition switch.
Slam Locking
With the introduction of CDL, slam locking of the drivers door is disabled. If an attempt is made to slam lock the
vehicle, the anti-theft alarm ECU will unlock all doors.
CDL Using the Drivers Door Sill Button
Each door has a sill button to allow that door to be individually locked from inside the vehicle. The drivers door sill
button has additional functionality which allows all doors to be locked from inside the vehicle from this one button.
When the driver door sill lock button is depressed, the CDL system enters a sill locked state, where all doors are
locked but immobilisation and perimetric and volumetric sensing is suspended. CDL using the drivers sill lock
button can be achieved with or without the key in the ignition switch and without the ignition being on.
If the CDL is in the sill locked state and the lock button on the remote handset is pressed, the volumetric and
perimetric functions of the alarm system will become active and active engine immobilisation will be invoked.
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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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