1999 LAND ROVER DEFENDER fuse box

ELECTRICAL
9
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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86ELECTRICAL
12
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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ELECTRICAL
15
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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86ELECTRICAL
20
DESCRIPTION AND OPERATION HEATED FRONT SCREEN - FROM 02MY
1.Heated front screen RH connector
2.Heated front screen LH connector
3.Heated front screen ECU (behind instrument pack)
4.Heated front screen relay (passenger compartment fuse box)
5.Heated front screen switch
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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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86ELECTRICAL
22
DESCRIPTION AND OPERATION HEATED FRONT SEATS - FROM 02MY
1.LH and RH seat heater switches
2.Seat heater cushion and squab elements
3.Seat heat/Window lift relay (passenger compartment fuse box)
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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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