1999 LAND ROVER DISCOVERY air suspension

PANEL REPAIRS
REPAIRS 77-2-31
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. Models with A/C: Fit A/C pipes and recharge
A/C system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
2.Fit harness to valance.
3.Fit ABS modulator.

+ BRAKES, REPAIRS, Modulator unit
- ABS.
4.Fit PAS/ACE reservoir and refill fluids to correct
levels.

+ FRONT SUSPENSION,
ADJUSTMENTS, ACE hydraulic system
bleeding.

+ CAPACITIES, FLUIDS,
LUBRICANTS AND SEALANTS, Fluids.
5.Fit air filter assembly.

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

+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
6.Fit front wing.

+ EXTERIOR FITTINGS, REPAIRS,
Wing - front - up to 03MY.

+ EXTERIOR FITTINGS, REPAIRS,
Wing - front - from 03MY.
7.Connect leads/multiplug to alternator.
8.Connect battery leads, negative lead last.
M77 1744
M77 1689A

PANEL REPAIRS
77-2-38 REPAIRS
Sill outer assembly
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove RH or LH front wing.

+ EXTERIOR FITTINGS, REPAIRS,
Wing - front - up to 03MY.
4.Remove RH or LH front door.

+ DOORS, REPAIRS, Door - front.
5.Remove RH or LH rear door.

+ DOORS, REPAIRS, Door - rear.
6.Remove RH or LH sill finisher.
7.Remove RH or LH 'A' post inner lower
finishers.
8.Remove RH or LH front seat.

+ SEATS, REPAIRS, Seat - front.
9. LH side: Remove power amplifier and EAT
ECU.

+ IN CAR ENTERTAINMENT,
REPAIRS, Amplifier - power.
10. RH side: Remove CD autochanger.

+ IN CAR ENTERTAINMENT,
REPAIRS, CD autochanger.
11.Remove rear seats.

+ SEATS, REPAIRS, Seat - rear.
12.Remove RH or LH front seat belt.

+ RESTRAINT SYSTEMS, REPAIRS,
Seat belt - front.
13.Remove tread plates from front and rear door
apertures.
14.Release carpet and position aside.
15.Remove front and rear door aperture seals.
16.Release relevant wiring from 'A' post, 'B/C' post
and sill areas, and position aside.
17.Remove loadspace lower trim casing.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
18. RH side: Remove lower ACE accelerometer.

+ FRONT SUSPENSION, REPAIRS,
Accelerometer - ACE - lower.
19. LH side: Remove SLS air compressor unit.

+ REAR SUSPENSION, REPAIRS,
Compressor unit - air - SLS.
20. Models with rear A/C: Recover refrigerant
from A/C system and remove A/C pipes from
LH sill.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
21.Remove 2 bolts securing body to chassis.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 2 bolts securing body to chassis and tighten
to 45 Nm (33 lbf.ft).
2. Models with rear A/C: Fit A/C pipes to sill and
recharge A/C system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
3. LH side: Fit SLS air compressor unit.

+ REAR SUSPENSION, REPAIRS,
Compressor unit - air - SLS.
4. RH side: Fit lower ACE accelerometer.

+ FRONT SUSPENSION, REPAIRS,
Accelerometer - ACE - lower.
5.Fit loadspace lower trim casing.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
6.Fit relevant wiring to 'A' post, 'B/C' post and sill
areas.
7.Fit front and rear door door aperture seals.
8.Fit carpet and secure into position.
9.Fit tread plates to front and rear door apertures.
10.Fit front seat belt.

+ RESTRAINT SYSTEMS, REPAIRS,
Seat belt - front.
11.Fit rear seats.

+ SEATS, REPAIRS, Seat - rear.
12. LH side: Fit CD autochanger.

+ IN CAR ENTERTAINMENT,
REPAIRS, CD autochanger.
13. RH side: Fit power amplifier and EAT ECU.

+ IN CAR ENTERTAINMENT,
REPAIRS, Amplifier - power.
14.Fit front seat.

+ SEATS, REPAIRS, Seat - front.
15.Fit 'A' post inner lower finishers.
M77 1716A

CORROSION PREVENTION AND SEALING
CORROSION PREVENTION 77-4-7
The checks described above are intended to be visual only. It is not intended that the operator should remove trim
panels, finishers, rubbing strips or sound-deadening materials when checking the vehicle for corrosion and paint
damage.
With the vehicle on a lift, and using an inspection or spot lamp, visually check for the following:
lCorrosion damage and damaged paintwork, condition of underbody sealer on front and rear lower panels, sills
and wheel arches;
lDamage to underbody sealer. Corrosion in areas adjacent to suspension mountings and fuel tank fixings.
NOTE: The presence of small blisters in the underbody sealer is acceptable, providing they do not expose bare metal.
Pay special attention to signs of damage caused to panels or corrosion protection material by incorrect jack
positioning.
WARNING: It is essential to follow the correct jacking and lifting procedures.
With the vehicle lowered, visually check for evidence of damage and corrosion on all visible painted areas, in
particular the following:
lFront edge of bonnet;
lVisible flanges in engine compartment;
lLower body and door panels.
Rectify any bodywork damage or evidence of corrosion found during inspection as soon as is practicable, both to
minimise the extent of the damage and to ensure the long term effectiveness of the factory-applied corrosion
prevention treatment. Where the cost of rectification work is the owner's responsibility, the Dealer must advise the
owner and endorse the relevant documentation accordingly.
Where corrosion has become evident and is emanating from beneath a removable component (e.g. trim panel,
window glass, seat etc.), remove the component as required to permit effective rectification.
Underbody protection repairs
Whenever body repairs are carried out, ensure that full sealing and corrosion protection treatments are reinstated.
This applies both to the damaged areas and also to areas where protection has been indirectly impaired, as a result
either of accident damage or repair operations.
Remove corrosion protection from the damaged area before straightening or panel beating. This applies in particular
to panels coated with wax, PVC underbody sealer, sound deadening pads etc.
WARNING: DO NOT use oxy-acetylene gas equipment to remove corrosion prevention materials. Large
volumes of fumes and gases are liberated by these materials when they burn.
NOTE: Equipment for the removal of tough anti-corrosion sealers offers varying degrees of speed and effectiveness.
The compressed air-operated scraper (NOT an air chisel) offers a relatively quiet mechanical method using an
extremely rapid reciprocating action. Move the operating end of the tool along the work surface to remove the material.
The most common method of removal is by means of a hot air blower with integral scraper.
Another tool, and one of the most efficient methods, is the rapid-cutting 'hot knife'. This tool uses a wide blade and is
quick and versatile, able to be used easily in profiled sections where access is otherwise difficult.
Use the following procedure when repairing underbody coatings:
1Remove existing underbody coatings
2After panel repair, clean the affected area with a solvent wipe, and treat bare metal with an etch phosphate
material
3Re-prime the affected area
CAUTION: DO NOT, under any circumstances, apply underbody sealer directly to bare metal surfaces.
4Replace all heat-fusible plugs which have been disturbed. Where such plugs are not available use rubber
grommets of equivalent size, ensuring that they are embedded in sealer
5Mask off all mounting faces from which mechanical components, hoses and pipe clips, have been removed.
Underbody sealer must be applied before such components are refitted
6Brush sealer into all exposed seams
7Spray the affected area with an approved service underbody sealer
8Remove masking from component mounting faces, and touch-in where necessary. Allow adequate drying time
before applying underbody wax

CORROSION PREVENTION AND SEALING
SEALING 77-4-9
SEALING
Body Sealing
Underbody sealer treatment areas
Underfloor areas and sill outer panels are treated with a Plastisol PVC underbody sealer. This material is not suitable
for re-treatment. When repairing areas of underbody sealer, strip the factory-applied underbody sealer back to a
suitable break point. Ensure that a clean metal surface is exposed and that the edge of the existing sealer adheres
soundly to the panel.
Apply new underbody sealer between primer and surfacer paint operations. Apply seam sealer as necessary before
application of underbody sealer. Ensure that blanking plugs and grommets in the floor pan (except those used for wax
injection) are fitted before underbody sealer application. Refit any heat-fusible plugs which have been disturbed in
repair with the aid of a hot air blower, or replace with rubber grommets.
CAUTION: Ensure that suspension units, wheels, tyres, power unit, propeller shafts, exhaust and brakes
(including all mounting points) are shielded prior to application of fresh underbody sealer.

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-17
The existence of an intermediate state causes a fault code to be detected by the BCU. To reduce the chances of the
fault condition occurring while changing selector lever position, the inputs are debounced and only considered valid
when they have existed for at least 33 ms.
Transmission neutral selector
The transmission neutral sensor provides an earth signal to the BCU when the transfer box is in neutral. The earth
signal causes the BCU to operate an audible warning when the transfer box is in neutral with the ignition switched on.

+ TRANSFER BOX - LT230SE, DESCRIPTION AND OPERATION, Description.
Self levelling suspension and ABS
The BCU communicates with the SLABS ECU for several functions:
lAn output is provided from the SLABS ECU to the BCU to provide the logic conditions for issuing the SLS audible
warning.
lThe BCU receives an input from the SLABS ECU relating to the raise/ lower command from the remote handset.

+ REAR SUSPENSION, DESCRIPTION AND OPERATION, Description - SLS.
Hill descent control
The BCU provides an output signal to the SLABS ECU for automatic transmission in neutral for HDC control. The
BCU checks the status of the ignition and 'gearbox state' inputs and provides a 'Neutral selected' output. If the ignition
is on and 'gearbox state' is Neutral, the 'Neutral selected' output is on, otherwise 'Neutral selected' is off.

+ BRAKES, DESCRIPTION AND OPERATION, Description.
Heated screens
The Heated Front Screen (HFS) is fitted for some market destinations and is operated from a non-latching switch
located on the instrument pack cowl. The BCU will only allow the heated front screen to operate when the engine is
running and controls the time-out period for switching the circuit off.
The heated front screen operation can also be controlled from the Automatic Temperature Control (ATC) ECU on
vehicles fitted with air conditioning.
The heated rear window will only function when the engine is running, and is operated by a non-latching switch on the
instrument pack cowl. The heated rear window can also be operated by the ATC ECU on vehicles fitted with air
conditioning.
Interior courtesy lamps
The BCU controls the operation of the interior courtesy lamps. The courtesy lamps are situated in the front, mid and
rear areas of the headlining.
Fuel flap actuator
The BCU provides an earth path to the fuel flap release solenoid to allow the fuel filler flap to be opened. This is only
allowed if the alarm system is not set and all other conditions have been satisfied. The fuel flap release switch is
located in the fascia switch pack on vehicles up to 2003 model year or in the instrument pack binacle on vehicles from
2003 model year. The switch receives a voltage supply from the passenger compartment fuse box.