1999 LAND ROVER DEFENDER ignition

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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ELECTRICAL
21
DESCRIPTION AND OPERATION The Heated Front Screen (HFS) is a new feature for 2002MY which is available as part of a cold climate pack on
Td5 engine variants only. The HFS system comprises an HFS ECU, an HFS relay, a controlling switch and the
HFS elements.
The HFS comprises two elements laminated in the windscreen. The elements are connected by bus bars within
the screen and therefore the HFS has only one feed and one earth connector.
The HFS is controlled by the HFS ECU which determines when HFS operation is permitted. The ECU also has a
timer which allows HFS operation for up to 8 minutes. The HFS ECU is located behind the instrument pack,
adjacent to the dim/dip relay. The ECU is connected by a multiplug. The ECU receives an ignition feed via the
satellite fuse box and an engine running signal from the engine oil pressure switch.
A non-latching switch for HFS operation is located in the fascia. The switch has a tell-tale lamp to indicate when
the HFS screen is operative.
The HFS relay is located in the under seat fuse box and receives a permanent battery voltage supply via fusible
link 1 in the under seat fuse box. The relay coil is connected to the HFS ECU and an earth point. When the relay is
operated, battery voltage is supplied from the relay, via fuse 25 in the passenger compartment fuse box to the
HFS element.
When the HFS switch is depressed, a momentary earth path is completed from the HFS ECU, through the switch
to earth. This is sensed by the ECU as a request for HFS operation. If the ECU receives an ignition on signal and
an oil pressure signal, it allows HFS operation. The ECU provides an output to the coil of the HFS relay. When the
coil is energised, the contacts close and battery voltage, via fusible link 1 in the under seat fuse box is supplied to
the HFS element, via fuse 25 in the passenger compartment fuse box. The feed is also supplied via a splice joint
to the HFS switch to illuminate the tell tale lamp in the switch.
The HFS ECU will allow screen operation for up to 8 minutes, after which it removes the feed to the HFS relay
coil, which, after the contacts open, removes the supply to the HFS element and simultaneously extinguishing the
tell tale lamp in the switch. If, during the timed operation period, the HFS ECU receives an additional request
signal from operation of the switch, HFS operation is stopped.
When operating, the HFS element draws approximately 25 Amps. To prevent excess drain on the vehicle battery,
if the ignition on signal and/or the oil pressure switch (engine running) signal is lost, the HFS ECU de-energises, if
already operating, or will not energise the HFS relay.
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ELECTRICAL
23
DESCRIPTION AND OPERATION Heated front seats are a new feature for 2002MY and are available as part of a cold climate pack on Td5 engine
variants only. The heated seats system comprises, two latching switches, a seat relay and heater elements.
The latching switches are located in the fascia. Each switch individually controls its related seat heater elements.
Each switch contains a tell tale lamp to indicate when the seat heaters are active. There is no timer function for the
seat heater operation and the seat heaters will remain active for as long as the switch is latched in and the ignition
is in position II.
The seat heater relay is located in the passenger compartment fuse box and shares its supply and operation with
the front window lift system. The relay receives a permanent battery voltage supply via fusible links 1 and 3 in the
under seat fuse box and fuse 28 in the satellite fuse box. The relay coil is connected to the ignition switch via fuse
7 in the passenger compartment fuse box and an earth point. When the ignition switch is moved to position II, the
relay coil is energised and the contacts close. Power is supplied from the relay to each of the seat heater
switches.
The heater elements are fitted in the seat cushion and squab on the drivers and passenger front seats and are
wired in series. The wiring looms for the elements is long enough to allow the seat squab to be lifted for access to
the under seat fuse box or the storage bin/battery without straining the wiring. The centre seat, if fitted, does not
have heater elements.
The cushion element receives the feed from the switch and contains a thermostatically controlled switch. When
the element temperature reaches 37±3°C (98±3°F) the thermostat cuts the supply to the cushion and squab
elements for that seat. As the temperature of the element falls to 28±3°C (82±3°F), the thermostat will close the
switch contacts allowing power to flow to both elements causing them to heat up again. In this way the thermostat
maintains the cushion and squab element temperatures between the figures stated.
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ELECTRICAL
25
DESCRIPTION AND OPERATION Electric window lift is a new feature for 02MY. The electric windows are only available on the front driver and
passenger doors. Rear passenger doors retain the manual window lift regulator mechanism.
The window lift system comprises a window motor in each front door, two window lift switches located in the fascia
switch panel and a relay, located adjacent to the passenger compartment fusebox. The windows are only
operative when the ignition switch is in position II.
Each window lift motor is located in the door, behind the trim casing. The motor and regulator form a handed
assembly and are not available separately as serviceable items.
The window lift relay receives a permanent battery feed via fusible links 1 and 3 in the under seat fuse box. The
relay coil has one side connected to earth with the other side receiving a feed from the ignition switch position II.
When the ignition is in position II, the relay is energised and battery voltage is supplied to each of the window lift
switches. On vehicles with heated seats, the relay is shared with the heated seat circuit.
Each switch has two wires to its applicable motor. When the switch is operated in either the up or down position,
one wire is supplied with a feed and the other is connected to earth as applicable for the selection made.
Each motor has thermal cut-out protection. If the window reaches the top or bottom limit of its travel or an object
obstructs the window, the thermal cut-out will sense the increased load on the motor and cut the power supply to
the motor brush contacts.
The cut-out time is between 3.5 to 5.0 seconds, with a time to restart of between 1 to 10 seconds. These figures
are based on an ambient temperature of 20°C (68°F) and a voltage of 13.5V.
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ELECTRICAL
27
DESCRIPTION AND OPERATION UNDER SEAT FUSE BOX
FROM 02MY
1.A/C Relay (if fitted)
2.A/C relay (if fitted)
3.Glow plug relay
4.Main relay
5.Fuel pump relay
6.ABS Return pump relay
7.Fuse 7 - Central Door Locking (CDL) and BBUS
(20A)
8.Fuse 6 - Anti-theft alarm ECU (15A)
9.Fuse 5 - Main relay (30A)10.Fuse 4 - Fuel pump relay (20A)
11.Fuse 3 - Horn/HRW relay (20A)
12.Fuse 2 - Accessory socket (20A)
13.Fuse 1 - ABS ECU (30A)
14.Fusible link 6 - Lights (30A)
15.Fusible link 5 - Ignition switch/Starter relay (60A)
16.Fusible link 4 - ABS Pump relay (30A)
17.Fusible link 3 - Window lift/Seat heat relay (60A)
18.Fusible link 2 - Air conditioning (60A)
19.Fusible link 1 - Glow plugs/Heated front screen
(100A)
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86ELECTRICAL
8
REPAIR LAMP - FRONT FLASHER
Service repair no - 86.40.42
Remove
1.Remove 2 screws securing flasher lamp to front
wing.
2.Disconnect multiplug and remove lamp.
Refit
3.Position flasher lamp and connect multiplug.
4.Fit and tighten lamp securing screws.BATTERY - DISCONNECT - FROM 02MY
Service repair no - 86.15.99
Remove
1.Remove front seat cushion.
2.Release clip and remove battery cover.
3.Loosen bolt securing negative earth lead, do not
remove lead at this stage.
4.Fit ignition key, turn to position’II’. Turn ignition
off, remove key from lock and immediately
remove negative lead.
Refit
5.Connect negative lead to negative terminal and
tighten bolt to10 Nm (7 lbf.ft).
6.Fit and secure battery cover.
7.Fit seat cushion.
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