1999 LAND ROVER DISCOVERY wiring

RESTRAINT SYSTEMS
75-4 DESCRIPTION AND OPERATION
Driver airbag module
The driver airbag module is located in the steering wheel and is controlled by the DCU. A bag within the module
inflates to protect the driver in the event of a collision severe enough to deploy the system.
The driver airbag module connects to the steering column wiring harness via a rotary coupler.
Within the driver airbag module is a squib which, when given the correct current by the DCU, inflates the airbag by
initiating a chemical reaction. In deployment, the airbag inflates within a fraction of a second and then deflates at a
controlled rate as the weight of the driver presses against the bag. Vents in the bag control airbag deflation.
The DCU regularly applies a test current to the driver airbag squib to confirm continuity of the ignition circuitry.
The DCU is capable of detecting a short to ground, a short to battery and an open circuit for the driver airbag module
squib. It will also identify if the configuration of the DCU differs from that actually fitted to the vehicle.
The DCU also stores the following additional information on each fault:
lA count indicating the number of times the fault has occurred.
lA start time and an end time for the fault to indicate duration of the fault.

SEATS
76-5-4 DESCRIPTION AND OPERATION
Description - electric seats
General
All markets use the same electric seat system. Electically operated lumbar support is optional. The system consists
of an electrical sub-system and a mechanical sub-system.
The electrical sub-system consists of the following components:
lBCU.
lSeat power relays.
lSeat switch packs.
lSeat fore/ aft motors.
lSeat cushion front up/ down motors.
lSeat cushion rear up/ down motors.
lSeat squab motor.
lLumbar pump.
lLumbar deflate solenoid.
The mechanical sub-system consist of the following components:
lGear wheels.
lRack and pinion assemblies.
Seat power relay
Located beneath the seat, the seat power relay supplies battery voltage to the satellite fuse box. Operation of the
relays is controlled by the BCU.
Voltage to the seat power relays is from fuse 5 in the engine compartment fuse box. The BCU controls the earth for
the relay coils. Operating the seat power relays provides voltage to the satellite fuse box under each seat.
Satellite fuse box
Located beneath the seat, the satellite fuse box provides circuit protection for the wiring to the seat switches and
motors. It also protects the lumbar inflate and deflate circuits.
The seat power relay provides voltage directly to the 40A fuse in the satellite fuse box. Voltage from this fuse feeds
the seat switch pack. The 3A fuses in the satellite fuse box protect the wiring to the lumbar pump and lumbar deflate
solenoid. Voltage to the 3A fuses comes from the seat switch pack.

PANEL REPAIRS
REPAIRS 77-2-21
REPAIRS
Front bulkhead assembly
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove front wing.

+ EXTERIOR FITTINGS, REPAIRS,
Wing - front - up to 03MY.
4.Remove washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
5. Models with A/C: Remove condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
6. Diesel models: Remove gearbox fluid cooler.
7.Remove RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
8.Release headlamp levelling motors and
position aside.
9.Release headlamp wiring and position aside.
10.Remove battery.

+ CHARGING AND STARTING,
REPAIRS, Battery.
11.Remove battery tray.
12.Remove air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
13.Remove 2 earth leads from LH of front
bulkhead.
14.Remove RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
15. Models with A/C: Release and remove A/C
pipes.
16.Remove RH and LH crush cans.
17.Remove bonnet release cable.
18.Support bonnet in open position
19.Remove bonnet locking mechanism.
20.Remove VIN plate.
21.Remove 2 bolts securing front bulkhead
assembly to chassis.
22.Remove centre braces.Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit centre braces.
2.Fit 2 bolts securing bulkhead to chassis and
tighten to 45 Nm (33 lbf.ft).
3.Fit VIN plate.
4.Fit bonnet locking mechanism.
5.Fit bonnet release cable.
6.Fit crush cans.
7. Models with A/C: Fit A/C pipes.
8.Fit RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
9.Fit 2 earth leads to LH of front bulkhead.
10.Fit air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
11.Fit battery tray.
12.Fit battery. Do not connect leads.

+ CHARGING AND STARTING,
REPAIRS, Battery.
13.Fit headlamp wiring and headlamp levelling
motors.
14.Fit RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
15. Diesel models: Fit gearbox fluid cooler.
16. Models with A/C: Fit condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
17.Fit washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.

PANEL REPAIRS
REPAIRS 77-2-23
Bonnet locking platform
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove front bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
4. Models with A/C: Remove condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Remove RH and LH repeater lamps.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
8.Release headlamp wiring and position aside.
9.Remove battery.

+ CHARGING AND STARTING,
REPAIRS, Battery.
10.Remove battery tray.
11.Remove air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
12.Remove RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
13.Remove bonnet release cable.
14.Support bonnet in open position
15.Remove bonnet locking mechanism.
16.Remove VIN plate.
17.Remove centre braces.Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit centre braces.
2.Fit VIN plate.
3.Fit bonnet locking mechanism.
4.Fit bonnet release cable.
5.Fit RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
6.Fit air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
7.Fit battery tray.
8.Fit battery. Do not connect leads.

+ CHARGING AND STARTING,
REPAIRS, Battery.
9.Fit headlamp wiring.
10.Fit RH and LH repeater lamps.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
11.Fit RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
12. Diesel models: Fit gearbox fluid cooler.
13. Models with A/C: Fit condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
14.Fit bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
15.Connect leads/multiplug to alternator.
16.Connect battery leads, negative lead last.

PANEL REPAIRS
77-2-24 REPAIRS
Front cross member
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
4. Models with A/C: Remove condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Release headlamp levelling motors and
position aside.
8.Release headlamp wiring and position aside.
9.Remove RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
10. Models with A/C: Release and remove A/C
pipes.
11.Remove RH and LH crush cans.
12.Remove 2 bolts securing front bulkhead
assembly to chassis.
13.Remove centre braces.
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.Refit
1.Fit centre braces.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit crush cans.
4. Models with A/C: Fit A/C pipes.
5.Fit RH horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
6.Fit headlamp wiring and headlamp levelling
motors.
7.Fit RH and LH headlamps.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
8. Diesel models: Fit gearbox fluid cooler.
9. Models with A/C: Fit condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
10.Fit washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
11.Connect leads/multiplug to alternator.
12.Connect battery leads, negative lead last.

PANEL REPAIRS
REPAIRS 77-2-25
Headlamp mounting panel - RH
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove front bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
4. Models with A/C: Remove condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove RH headlamp.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Remove RH repeater lamp.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
8.Release headlamp levelling motor and position
aside.
9.Release headlamp wiring and position aside.
10.Remove battery and battery tray.

+ CHARGING AND STARTING,
REPAIRS, Battery.
11.Remove horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
12.Remove RH crush can.
13.Remove 2 bolts securing front bulkhead
assembly to chassis.
14.Remove RH centre brace.Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit centre brace.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit crush can.
4. Models with A/C: Fit A/C pipes.
5.Fit horn.

+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
6.Fit battery and battery tray. Do not connect
leads.

+ CHARGING AND STARTING,
REPAIRS, Battery.
7.Fit headlamp wiring and headlamp levelling
motors.
8.Fit repeater lamp.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
M77 1741A

PANEL REPAIRS
77-2-26 REPAIRS
9.Fit headlamp.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
10. Diesel models: Fit gearbox fluid cooler.
11. Models with A/C: Fit condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
12.Fit bumper assembly.

+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
13.Connect leads/multiplug to alternator.
14.Connect battery leads, negative lead last.
Headlamp mounting panel - LH
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
4. Models with A/C: Remove condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove headlamp.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Remove repeater lamp.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
8.Release headlamp levelling motor and position
aside.
9.Release headlamp wiring and position aside.
10.Remove air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
11.Remove 2 earth leads from LH of front
bulkhead.
12.Release and remove A/C pipes.
13.Remove crush can.
14.Remove bonnet release cable.
15.Remove 2 bolts securing front bulkhead
assembly to chassis.
16.Remove centre brace.

PANEL REPAIRS
REPAIRS 77-2-27
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.Refit
1.Fit centre brace.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit bonnet release cable.
4.Fit crush can.
5. Models with A/C: Fit A/C pipes.
6.Fit 2 earth leads to LH of front bulkhead.
7.Fit air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
8.Fit battery tray.
9.Fit headlamp wiring and headlamp levelling
motors.
10.Fit repeater lamp.

+ LIGHTING, REPAIRS, Lamp - front
repeater - up to 03MY.
11.Fit headlamp.

+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
12. Diesel models: Fit gearbox fluid cooler.
13. Models with A/C: Fit condensor.

+ AIR CONDITIONING, REPAIRS,
Condenser.
14.Fit washer reservoir.

+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
15.Connect leads/multiplug to alternator.
16.Connect battery leads, negative lead last.