1999 LAND ROVER DISCOVERY key battery

RESTRAINT SYSTEMS
REPAIRS 75-23
Airbag module - passenger
$% 76.74.02
WARNING: It is imperative that before any work
is undertaken on the SRS system the appropriate
information is read thoroughly.
WARNING: Always disconnect both battery leads
before beginning work on the SRS system.
Disconnect the negative battery lead first. Never
reverse connect the battery.
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Release guides supporting glove box.
3.Lower glove box to gain access to air bag
module.4.Disconnect multiplug from air bag module.
5.Remove 4 Torx bolts securing air bag module
to fascia.
6.Remove air bag module from fascia panel.
WARNING: Store the air bag module with
the deployment side uppermost. If it is
stored deployment side down, accidental
deployment will propel the air bag module
with enough force to cause serious injury.
WARNING: Store the air bag module or seat
belt pre-tensioner in a designated storage
area. If there is no designated storage area
available, store in the luggage compartment
of the vehicle and inform the workshop
supervisor.
Refit
NOTE: If the air bag module is to be replaced,
the bar code of the new module must be
recorded.
1.Fit air bag module to fascia and tighten Torx
bolts to 8 Nm (6 lbf.ft).
2.Connect multiplug to air bag module.
3.Position glove box and engage supporting
guides. Close glove box.
4.Connect battery leads, earth lead last.

RESTRAINT SYSTEMS
75-24 REPAIRS
DCU
$% 76.74.06
WARNING: It is imperative that before any work
is undertaken on the SRS system the appropriate
information is read thoroughly.
WARNING: Always disconnect both battery leads
before beginning work on the SRS system.
Disconnect the negative battery lead first. Never
reverse connect the battery.
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Remove centre console.
lOn manual gearbox models:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - manual
models.
lOn automatic gearbox models:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - automatic
models.
3.Disconnect multiplug from DCU.
4.Remove 3 Torx bolts securing DCU to body and
remove DCU.
CAUTION: The SRS diagnostic control unit
is a non-serviceable component and no
attempt should be made to repair or modify
the unit.Refit
CAUTION: The SRS diagnostic control unit
is a shock sensitive device and must be
handled with extreme care.
1.Position DCU to body and connect multiplug.
2.Fit and tighten DCU Torx bolts to 10 Nm (7
lbf.ft).
3.Fit centre console.
lOn manual gearbox models:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - manual
models.
lOn automatic gearbox models:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - automatic
models.
4.Connect battery leads, earth lead last.

RESTRAINT SYSTEMS
REPAIRS 75-29
Rotary coupler
$% 76.74.20
WARNING: It is imperative that before any work
is undertaken on the SRS system the appropriate
information is read thoroughly.
WARNING: Always disconnect both battery leads
before beginning work on the SRS system.
Disconnect the negative battery lead first. Never
reverse connect the battery.
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Remove steering wheel.

+ STEERING, REPAIRS, Steering
wheel.
3.Remove steering column nacelle.

+ STEERING, REPAIRS, Nacelle -
steering column.4.Release rotary coupler multiplug from bracket
and disconnect from harness.
5.Disconnect rotary coupler multiplug from
harness.
6.Remove rotary coupler.
Refit
1.Fit rotary coupler to steering column and
connect multiplug to harness.
2.Connect rotary coupler multiplug to harness
and secure to bracket.
3.Fit steering column nacelle.

+ STEERING, REPAIRS, Nacelle -
steering column.
4.Fit steering wheel.

+ STEERING, REPAIRS, Steering
wheel.

INTERIOR TRIM COMPONENTS
76-3-10 REPAIRS
Fascia
$% 76.46.23/99
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Remove radio cassette player.

+ IN CAR ENTERTAINMENT,
REPAIRS, Radio.
3.Remove steering wheel.

+ STEERING, REPAIRS, Steering
wheel.
4.Remove steering column nacelle.

+ STEERING, REPAIRS, Nacelle -
steering column.
5.Remove centre console.
lFor models with automatic gearbox:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - automatic
models.
lFor models with manual gearbox:

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Console - centre - manual
models.
6.Remove 'A' post trim panels.
7.Remove 6 clips securing both lower closing
panels to fascia and remove closing panels.
8.Remove mats from fascia.
9.Remove 2 screws and release instrument cowl
from 2 clips on fascia.
10.Disconnect multiplugs from switches in
instrument cowl and remove cowl.
11.Remove 4 screws securing instrument pack to
fascia.
12.Disconnect 2 multiplugs from instrument pack
and remove pack.

LIGHTING
ADJUSTMENTS 86-2-1
LIGHTING ADJUST ME NTS
Headlamps beam alignment - up to 03MY
$% 86.40.17
Check
1.Ensure vehicle is unladen and tyres are at
correct pressures.
2. Models with SLS: Ensure vehicle is at
standard ride height.
3. Models with headlamp levelling: Ensure
headlamp levelling switch is set to '0'.
4.Align suitable beam setting equipment to
headlamp.
5.Switch headlamps on and measure main beam
settings. Beam must be 1.4% below the
horizontal and parallel to the vehicle centre line.
If necessary, adjust headlamp to get correct
beam settings.
6.Align beam setting equipment to 2nd headlamp
and repeat check.
7.Switch off headlamps and remove beam setting
equipment.Adjust
1. For RH headlamps: Release fixings and
remove battery cover
2.Remove headlamp access cover.
3.Turn vertical adjuster as necessary to get
correct beam setting. Use a 7 mm Allen key for
models with headlamp levelling, or a 10 mm
spanner for models without headlamp levelling.
4.Turn horizontal adjuster as necessary to get
correct beam setting. Use a 10 mm spanner.
5.Fit headlamp access cover.
6. For RH headlamp adjustment: Fit battery
cover and secure fixings.

LIGHTING
REPAIRS 86-2-13
Switch - hazard warning
$% 86.65.50
Remove
1.Carefully remove switch.
2.Disconnect multiplug from switch.
3.Remove switch.
Refit
1.Connect multiplug switch.
2.Position switch and push to secure.
Switch - indicator and exterior lighting -
combined
$% 86.65.55
WARNING: Always remove the key from the
starter switch, disconnect the vehicle battery and
wait 10 minutes before commencing work on the
SRS system.
Remove
1.Remove rotary coupler.

+ RESTRAINT SYSTEMS, REPAIRS,
Rotary coupler.
2.Remove 2 screws securing switch.
3.Carefully raise edge of switch bracket to clear
location peg and release switch from bracket.
4.Disconnect 2 multiplugs and remove switch.
Refit
1.Position switch and connect multiplugs.
2.Fit switch to bracket and secure with screws.
3.Fit rotary coupler.

+ RESTRAINT SYSTEMS, REPAIRS,
Rotary coupler.

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-1
BODY CONTROL UNIT DESCRIPTION AND OPERAT ION
Description
General
The Body Control Unit (BCU) is located behind the passenger glovebox and is connected to the main harness by four
connectors on its bottom edge and an additional connector located on the side of the BCU casing. Mounting the BCU
behind the fascia makes it reasonably inaccessible for intruders to disable the anti-theft system.
The BCU uses solid-state microprocessor control to perform logical operations and timing functions for a variety of
the vehicle's electrically operated systems, these include:
lDoor locking.
lAnti-theft alarm and immobilisation system.
lExterior lighting including direction indicators and hazard warning lamps.
lCourtesy lighting.
lWipers and washers.
lElectric windows and sunroof.
lHeated windows.
The BCU also communicates with several other electronically controlled systems such as the EAT ECU and SLABS
ECU and also has a datalink between the Intelligent Driver Module (IDM) and the instrument pack. The datalink is a
low speed bus capable of transmitting and receiving messages at a data rate of 10,400 bits per second. Additional
inputs and outputs to peripheral devices are included which are necessary for determining vehicle status for particular
logical operations e.g. crank, ignition key inserted, fuel flap enable etc.
The BCU receives its power supply from the engine compartment fuse box, and is protected by a 10 A fuse.
The BCU communicates with the IDM to provide the control signals to perform power switching operations in
conjunction with dedicated relays.
IDM
The IDM is integrated into the passenger compartment fuse box, which is mounted behind the fascia below the
steering column. There are no harnesses between the fuse box and the IDM. The IDM performs the power switching
operations for several of the vehicle's electrical systems.
The IDM communicates with the BCU and the instrument pack via a serial interface. If the BCU or the IDM is replaced,
the communications link between the two units has to be re-established. This can be done either by switching on the
ignition and leaving it on for five minutes, or by using TestBook. The vehicle immobilisation will remain active until the
communications link between the BCU and IDM has been re-established.
Transit mode
To prevent excessive battery drain during transit to overseas markets, the vehicle is placed in a transit mode. The
following functions are disabled when the vehicle is in transit mode:
lVolumetric sensors.
lPassive immobilisation.
lImmobilisation of the vehicle by use of door lock.
lIgnition key interlock.
lElectric seat enable time-out with driver's door open.

BODY CONTROL UNIT
86-3-2 DESCRIPTION AND OPERATION
Power supply
Battery supply to the BCU and the IDM is provided through a 10 A fuse located in the engine compartment fuse box.
The BCU unit receives an ignition switched power supply (ignition switch position II) input via a 10 A fuse in the
passenger compartment fuse box.
The BCU receives a signal when the ignition switch is turned to the crank position, it then supplies an earth path to
the starter relay coil, to enable the crank operation by supplying power through the starter relay contacts to the starter
motor.
Battery voltage is monitored and BCU operation will function normally between 8 and 18 volts. Between 5.7 and 8
volts the BCU is in the 'under volts' state. The status of the battery is used to determine which outputs may be driven.
If a voltage supply above 18 volts is experienced, outputs will not normally be driven except for those functions which
are required during cranking (robust immobilisation, antenna coil, crank enable relay and feed to gear position switch
contacts W, X, Y, Z). In the over voltage state the vehicle can be driven, but all other functions are disabled and
outputs are switched off (power windows, heated screen, direction indicators etc.).
All functions are disabled on power up until communications between the BCU and IDM have been established. If
communications cannot be established, operation will commence with degraded functionality.
Battery supply to the IDM is provided through the inertia switch and a 10 A fuse in the engine compartment fuse box.
If the inertia switch contacts are closed battery voltage is available at the IDM; if the inertia switch contacts are open
there is no battery supply to the IDM. The supply condition of the IDM is signalled to the BCU via the serial bus. If the
inertia switch is operated (contacts open) the change in state is detected by the BCU which unlocks the doors if the
ignition switch is in position II and the alarm is not set.
The BCU is earthed through a hard-wire connection.
Inputs and outputs
The BCU and IDM process inputs and provide the necessary outputs for control and operation of the vehicle's 'body'
systems.
BCU inputs
The BCU processes signals received from the following components:
lDoor latch switches.
lDriver's door key lock/ unlock switches.
lBonnet activated security system.
lVolumetric sensors.
lCentral Door Locking (CDL) switches.
lRemote transmitter (via receiver unit).
lInertia fuel cut-off switch.
lIgnition switch.
lFuel flap release switch.
The input voltages (V
in) for BCU digital signals are defined as follows:
lLogic 1 when V
in ≥ 6V.
lLogic 0 when V
in ≤ 2V.
BCU input voltages between 2 and 6 volts are indeterminate and cannot be guaranteed.
Analogue input voltages are measured as a ratio with respect to battery voltage.