1995 LAND ROVER DISCOVERY bonnet

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DESCRIPTION AND OPERATION ALARM COMPONENT LOCATIONS (96 MODELS)
COMPONENT LOCATION
1. Electronic control unit (ECU) and relays Under dash (passenger side).................
2. Anti-theft alarm indicator light Instrument panel..................................
3. Engine immobilisation warning light (EIWL) * Instrument panel..........
4. Passive coil Over starter switch barrel.............................................................
5. Bonnet switch RH engine compartment..........................................................
6. Door switches
7. Ultrasonic sensor Interior light switch panel....................................................
8. Lock barrel, sill buttons
9. Handset and key
10. Battery backed-up sounder or horn * RH engine compartment......................
11. Immobilisation unit (spider) * Above heater...................................
12. Aerial Part of fascia harness.......................................................................
* where applicable

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DESCRIPTION AND OPERATION DETECTION COMPONENTS
Switches
Perimetric protection for the vehicle is provided by
ECU inputs connected to the following:
Key switches (including starter)
Sill buttons
Bonnet switch
Door switches
Ultrasonic sensor
The ultrasonic sensor is located on the interior light
switch panel and triggers the alarm if movement is
detected.
WARNING INDICATORS
Battery backed-up sounder
The battery backed-up sounder is located in the
engine compartment and provides an audible warning
whenever the alarm is triggered.
NOTE: Disconnecting the vehicle battery
will result in the alarm sounding if the
correct procedure has not been followed.
See Repair, Battery.
Engine immobilisation warning light (EIWL)
The engine immobilisation warning light is located in
the instrument pack and provides a visual indication
that the engine is immobilised.
Anti-theft alarm indicator light
The anti-theft alarm indicator light is located in the
instrument pack and provides a visual indication of the
alarm status.
Inertia switch and central door locking
As a safety feature, the alarm system is designed to
recognise the inertia switch and via the ECU, unlock
the doors in the event of a collision.
NOTE: This feature only applies when the
starter switch is in the on position.ANTI-THEFT ALARM OPERATION (96 MODELS)
Full arming and immobilisation
Locking the vehicle using the handset immobilises the
engine and initializes both volumetric and perimetric
protection, providing:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which no
movement is detected inside the vehicle;
2.No door or bonnet is open.
NOTE: If either of the above conditions are
not satisfied, the alarm will only be
partially armed. This is a mislock condition
which will be made apparent by a delay of 10
seconds before the anti-theft alarm indicator
begins to flash.
Disarming the alarm
NOTE: ALWAYS disarm the alarm using
the handset.
Unlocking with the key will not disarm the alarm or
mobilise the vehicle. If the handset fails to unlock the
vehicle
See Repair, Handset.
Partial arming and immobilisation
The alarm will be partially armed and the engine
immobilised if the vehicle is locked with the handset or
key, if:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which movement
is detected inside the vehicle;
2.A door or bonnet is open.
NOTE: This is a mislock condition which
will be made apparent by a delay of 10
seconds before the anti-theft alarm
indicator begins to flash. Subsequent closure of
the offending aperture will cause the alarm to
attempt full arming as previously described.
Immobilisation
The vehicle will be automatically immobilised
whenever any of the following conditions occur:
1.The vehicle is locked using the handset.
2.The vehicle is locked using the key.
3.Thirty seconds after the starter switch has been
turned off AND the driver's door opened.
4.Five minutes after the starter switch is turned off
or the alarm disarmed.

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DESCRIPTION AND OPERATION ANTI-THEFT ALARM BUILT-IN TEST (96 MODELS)
NOTE: The handset should be detached
from the key to allow perimetric testing of
the alarm system. The system will
automatically switch to volumetric testing if the
handset is in close proximity to the starter switch.
The built-in test procedure can be accessed providing
the following conditions exist:
Alarm disarmed.
Ignition off.
Doors unlocked.
Bonnet[hood] closed.
The test mode can be entered by completing the
following instructions within 5 seconds:
1.Open bonnet.
2.Turn starter switch on.
3.Open driver's door (far enough to activate
switch).
4.Turn starter switch off.
5.Turn starter switch on.
If the test mode has been correctly accessed, the
sounder/horn will operate briefly and the anti-theft
alarm indicator and hazard warning lights will flash.
Perimetric tests
The anti-theft alarm indicator light and the hazard
warning lights will flash when:
1.Door switches are activated;
2.The bonnet is opened;
3.Sill switches are activated;
4.Key switches are activated.
NOTE: Operation of key switches can be
verified by turning the key in the relevent
direction so as not to simultaneously
activate the sill switch. If the key switch changes
state, the change should be detected but the sill
switch will not be activated.
Volumetric tests
Press the unlock button or move the handset close to
the starter switch to disable perimetric testing and
enable volumetric testing. If movement is detected
within the vehicle by the ultrasonic sensor it will be
indicated by flashing the anti-theft alarm indicator and
hazard warning lights.
NOTE: Exit anti-theft alarm built-in test by
turning starter switch to the off position.

ELECTRICAL
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FAULT DIAGNOSIS GENERAL INFORMATION
The electrical fault diagnostic tool on Discovery
vehicles is Testbook. Detailed information of electrical
systems, component locations and circuit diagrams
are covered in the Discovery Electrical
Troubleshooting Manual.
See INTRODUCTION,
Information, Fault Diagnostic Equipment
This section covers checks of the charging and
ignition system.
GENERATOR TESTING
Service repair no - 86.10.01
Charging system check
1.Check battery is in good condition, with an open
circuit voltage of at least 12.6 V. Recharge or
substitute battery to carry out test.
2.Check drive belt condition.
See SECTION 10,
Maintenance, Under Bonnet [Hood]
Maintenance
3.Check battery connections are clean and tight.
4.Check generator connections are clean and
tight.
5.Ensure there is no drain on battery from, for
example, interior, under bonnet [hood] or door
edge lamps.
Generator test
Following instructions refer to use of suitable test
equipment using a carbon pile rheostat.
6.Connect test equipment referring to
manufacturer's instructions.
7.Start engine and run at 3000 rev/min without
accessory load.
8.Rotate carbon pile load control to achieve
greatest output (amps) without allowing voltage
to fall below 12.0 V. A reading in amps, of
generator output, minus 10% to allow for EFI
and Ignition loss, should be obtained.
9.Run engine at 3000 rev/min, switch selector to
regulator test, read voltmeter. A reading of 13.6
to 14.4 V should be obtained.
10.Switch selector to diode/stator test, switch on
headlamps to load generator. Raise engine
speed to 3000 rev/min, read voltmeter, needle
must be within 'OK' range.TESTING IN POSITION
Charging circuit resistance test.
1.Connect a low range voltmeter between
generator terminal marked B+ and positive
terminal of battery.2.Switch on headlamps, start engine. Run engine
at approximately 3000 rev/min. Note voltmeter
reading.
3.Transfer voltmeter connections to frame of
generator and negative terminal of battery, and
again note voltmeter reading.
4.If reading exceeds 0.5 volt on positive side or
0.25 volt on negative side, there is a high
resistance in charging circuit which must be
traced and remedied.

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REPAIR HANDSET INITIALISATION
NOTE: New handsets are supplied in pairs.
If a new handset is required, it will require
initialisation to the ECU using the
following procedure:
1.Starting conditions: ignition off, doors unlocked,
bonnet switch depressed.
2.Carry out instructions 3. to 9. within 8 seconds.
3.Switch ignition ON.
4.Switch ignition OFF.
5.Lock doors.
6.Unlock doors.
7.Release bonnet switch.
8.Switch ignition ON.
9.Switch ignition OFF.
If alarm is correctly accessed, horn will sound and
LED will light. It is now possible to programme two
handsets of correct frequency to vehicle alarm ECU.
This must be carried out within two minutes.
10.Press and hold down button on first handset until
dash LED flashes.
11.Repeat instruction 10. for second handset.
12.The LED will extinguish if both handsets have
been initialised correctly.CENTRAL DOOR LOCKING
Where electrically operated central door locking is
fitted, locking or unlocking the drivers door from
outside by key operation, or from the inside with the
sill knob automatically locks or unlocks the passenger
and rear doors.
Front and rear passenger doors can be independently
locked or unlocked from inside the vehicle by sill knob
operation but can be overidden by further operation of
the driver's door locking control.
On rear doors, where side facing fold down seats are
fitted, a child safety lock is provided which can be
mechanically pre-set to render the interior door
handles inoperative.
Failure of a door actuator will not affect the operation
of the remaining doors and the door with the
inoperative actuator can still be locked or unlocked
manually.
The actuator unit fitted to the driver's door is the
master actuator and is identified from the actuators
fitted to the passenger and rear doors by having a
white connecting link, whereas the passenger and
rear door actuators have grey coloured connecting
links.
NOTE: Actuator units are non-servicable, if
a fault should occur replace the unit with a
new one.

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REPAIR BONNET SWITCH
Service repair no - 86.55.89
Remove
1.Remove 2 bolts securing sounder, move
sounder aside.
2.Locate and disconnect bonnet switch multiplug.
3.Release and remove switch.
Refit
4.Reverse removal procedure.ULTRASONIC SENSOR
Service repair no - 86.77.32
Remove1.Release sensor from switch panel.
2.Disconnect multiplug and remove sensor.
Refit
3.Reverse removal procedure.
ANTI-THEFT ALARM INDICATOR LIGHT (96
MODELS)
Service repair no - 86.45.61
See Instrument illumination and warning light
bulbs
ENGINE IMMOBILISATION WARNING LIGHT (96
MODELS)
Service repair no - 86.45.61
See Instrument illumination and warning light
bulbs