oil LAND ROVER DEFENDER 1999 Workshop Manual

82AIR CONDITIONING
6
REPAIR Refit
20.Clean TXV and mating face.
21.Lubricate new’O’rings with refrigerant oil and fit
’O’rings to pipes.
22.Position TXV and tighten Allen screws.
23.Position evaporator and fit sensor.
24.Position cover and tighten screws.
25.Clean pipes and mating faces.
26.Lubricate and fit new’O’rings, position pipes
and tighten Allen screw.
27.Connect trinary switch multiplug.
28.Position blower unit,tighten screws and connect
multiplugs.
29.With assistance position A/C duct assembly to
vehicle.
30.Connect drain pipe to evaporator.
31.Connect multiplug to relay bracket.
32.Align A/C duct to fascia, tighten securing bolt
and screws.
33.Position speakers and connect Lucars.
34.Position relay bracket and tighten bolts.
35.Clean pipes and mating face.
36.Lubricate and fit new’O’rings to evaporator
pipes.
37.Position pipes and tighten bolts to6Nm(4
lbf.ft).
38.Renew receiver drier.See this Section.
39.Recharge A/C system.See Adjustment.
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84WIPERS AND WASHERS
4
DESCRIPTION AND OPERATION REAR WIPER - FROM 02MY
1.Rear wiper relay
The rear wiper system is unchanged except for the addition of a wiper motor relay into the electrical circuit.
The new rear wiper relay is located in the tail door, below the wiper motor. The relay coil is energised by a feed
supplied from the rear wiper switch. When the relay contacts close, a feed is supplied via the ignition switch
(position II) and a fuse in the passenger compartment fuse box, through the relay contacts to the wiper motor.
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ELECTRICAL
1
DESCRIPTION AND OPERATION SECURITY AND CENTRAL DOOR LOCKING
SYSTEM - FROM 02MY
The following description details the functionality and operation of the 10AS Security and Central Door Locking
(CDL) System fitted to 2002MY Defender. The system contains some new features and also retains some
features from previous Defender models. The alarm system and CDL system are controlled by the 10AS anti-theft
alarm ECU.
New door lock barrels are introduced and use the same key as the ignition switch barrel, thereby eliminating the
requirement for a separate key for the doors.
NOTE: Some markets will only have some of the features described and some will have no
security or central door locking functions.
The security system comprises the following components:
10AS anti-theft alarm ECU
Remote handset transmitters
Transponder coil
Volumetric sensor
CDL actuators
Bonnet switch
Driver’s door key barrel switch
Door switches
Bonnet switch
Battery Backed-Up Sounder (BBUS) or alarm sounder
Security LED
Engine immobilised warning lamp
Direction indicators
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86ELECTRICAL
2
DESCRIPTION AND OPERATION SECURITY AND CENTRAL DOOR LOCKING
SYSTEM COMPONENTS - FROM 02MY
1.Engine immobilisation warning lamp
2.Security LED
3.Transponder coil
4.CDL actuators (tail door shown)
5.Immobilisation ECU (300Tdi models only)
6.Remote handset and key7.Door switches
8.Bonnet switch
9.Alarm sounder
10.Battery Backed Up Sounder (BBUS)
11.Anti-theft alarm ECU
12.Volumetric sensor
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ELECTRICAL
7
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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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
13
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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86ELECTRICAL
16
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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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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