warning LAND ROVER DISCOVERY 1999 Workshop Manual

REAR SUSPENSION
REPAIRS 64-29
Road spring - rear
$% 64.20.01
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Support vehicle under chassis.
3.Remove road wheel.
4.Support weight of axle on a jack.
5.Remove bolt securing damper to axle.
WARNING: Make sure the axle cannot move
when the damper is disconnected. The
damper limits the downward movement of
the axle. If the axle is not restrained,
disconnecting the damper will allow
unrestricted movement which may cause
personal injury or damage to equipment.
6.Remove clip securing brake pipe to bracket.
7.Release ABS sensor lead from bracket.
8.Lower axle on jack and remove spring.Refit
1.Ensure spring seats are clean.
2.Fit spring with close coil uppermost.
3.Ensure spring is correctly located on spring
seats and raise axle. Fit and tighten bolt
securing damper to axle to 124 Nm (91 lbf.ft).
4.Fit clip to secure brake pipe to bracket.
5.Fit ABS sensor lead to bracket.
6.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
7.Remove stand(s) and lower vehicle.

REAR SUSPENSION
64-30 REPAIRS
Air spring - SLS
$% 64.21.01
Remove
1.Using TestBook, depressurise SLS air system.
After depressurisation, approximately 1 bar
(15 lbf.in
2) air pressure remains in the
system.
2.Raise rear of vehicle and support under
chassis.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
3.Remove road wheel.
4.Remove 2 clips securing air spring to chassis.
5.Collapse air spring and disconnect pipe from
top of air spring.
CAUTION: Always fit plugs to open
connections to prevent contamination.
6.Rotate air spring, to unlock from axle and
remove from vehicle.
7.Remove connector from pipe.Refit
1.Clean mating faces of air spring, axle and
chassis.
CAUTION: Check air bag for signs of
damage. If air bag is damaged, air spring
must be replaced.
2.Fit pipe connector to air spring.
3.Locate air spring on axle and rotate 90° to fully
engage bayonet fitting.
4.Connect pipe to top of air spring.
5.Engage top locating pins of air spring in chassis
and secure with clips.
6.Repressurise SLS air system using TestBook.
WARNING: Eye protection must be worn
during the repressurisation procedure.
7.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
8.Remove stand(s) and lower vehicle.

REAR SUSPENSION
REPAIRS 64-31
Damper - rear
$% 64.30.02
Remove
1.Raise rear of vehicle and support under
chassis.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove road wheel.
3.Support weight of axle on a jack.
4.Remove 2 bolts securing damper to axle and
chassis.
WARNING: Make sure the axle cannot move
when the damper is disconnected. The
damper limits the downward movement of
the axle. If the axle is not restrained,
disconnecting the damper will allow
unrestricted movement which may cause
personal injury or damage to equipment.
5.Compress damper and remove from vehicle.
Refit
1.Locate damper in axle and fit lower bolt, extend
damper to chassis and fit top bolt.
2.Tighten damper bolts to 125 Nm (92 lbf.ft).
3.Lower axle and remove jack.
4.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
5.Remove stand(s) and lower vehicle.
Bushes - radius arm
$% 64.35.29
Models with SLS:
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove road wheel(s).
3. Models with SLS: Remove nut and bolt
securing height sensor link to radius arm.
4.Remove nut and bolt securing radius arm to
chassis.
5.Remove 2 nuts securing radius arm to axle.
6.Remove rear bolt and lower radius arm.

REAR SUSPENSION
64-34 REPAIRS
Bushes - Watts linkage
$% 64.35.35
Models with SLS:
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove 3 nuts and bolts securing Watts
linkage to axle and chassis and remove Watts
linkage.
3.Remove 2 nuts and bolts securing transverse
links to pivot housing and remove links from
pivot housing. 4.Use LRT-60-010/1 and LRT-60-010/3 to press
bushes from transverse links and pivot
housing.
Refit
1.Clean bush locations in transverse links and
pivot housing.
2.Using LRT-60-010/1 and LRT-60-010/2press
new bushes into transverse links and pivot
housing.
3.Position transverse links to pivot housing and
tighten bolts to 155 Nm (114 lbf.ft).
4.Position Watts linkage to axle and chassis. Fit
bolts but do not tighten at this stage.
5.Remove stand(s) and lower vehicle.
6.Tighten bolts securing pivot housing to axle to
230 Nm (170 lbf.ft). Tighten bolts securing
transverse links to chassis to 140 Nm (103
lbf.ft).
CAUTION: Nuts and bolts must be tightened
with weight of vehicle on suspension.

REAR SUSPENSION
REPAIRS 64-35
Sensor - height - SLS
$% 64.36.01
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Disconnect height sensor multiplug.
3.Remove bolt securing height sensor link to
radius arm.
4.Remove 2 bolts securing height sensor to
chassis and remove height sensor.
Refit
1.Position height sensor to chassis and tighten
bolts to 6 Nm (4.4 lbf.ft).
2.Position height sensor link to radius arm and
tighten bolt to 25 Nm (18 lbf.ft).
3.Connect height sensor multiplug.
4.Remove stand(s) and lower vehicle.
5.Use TestBook to calibrate height sensor.
Compressor unit - air - SLS
$% 64.50.10
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Using TestBook, depressurise SLS air system.
After depressurisation, approximately 1 bar
(15 lbf.in
2) air pressure remains in the
system.
2.Release 2 fasteners and remove air
compressor unit cover.
3.Remove 2 bolts securing air compressor unit to
chassis. Release unit and lower onto blocks to
support the weight.
4.Noting their fitted position, disconnect pipes
from air valves.
CAUTION: Always fit plugs to open
connections to prevent contamination.

REAR SUSPENSION
64-36 REPAIRS
5.Disconnect inlet and exhaust pipes.
CAUTION: Always fit plugs to open
connections to prevent contamination.
6.Disconnect multiplugs from air valves, exhaust
valve and compressor.
7.Release and disconnect compressor multiplug
from casing.
8.Remove air compressor unit from vehicle.
9.Release supply/exhaust pipe.
CAUTION: Always fit plugs to open
connections to prevent contamination.
10.Remove 3 bolts securing compressor to
casing. Remove compressor and collect
mounting washers. Refit
1.Locate mounting washers and position
compressor in casing.
2.Apply sealant, Part No. STC 50552 to
compressor securing bolts. Fit bolts and tighten
to 7 Nm (5.2 lbf.ft).
3.Connect compressor multiplug to casing.
4.Connect supply/exhaust pipe.
5.Position air compressor unit on support block,
connect inlet and exhaust pipes.
6.Connect multiplugs to air valves, exhaust valve
and compressor.
7.Connect pipes to air valves.
8.Position air compressor unit to chassis and
engage casing in retaining lugs. Fit air
compressor unit securing bolts and tighten to
25 Nm (18 lbf.ft).
9.Ensure pipes are located in cut outs in casing.
10.Position air compressor unit cover and lock
fasteners.
11.Repressurise SLS air system using TestBook.
WARNING: Eye protection must be worn
during the repressurisation procedure.

REAR SUSPENSION
64-38 REPAIRS
Air valve - SLS
$% 64.50.47
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Using TestBook, depressurise SLS air system.
After depressurisation, approximately 1 bar
(15 lbf.in
2) air pressure remains in the
system.
2.Release 2 fasteners and remove air
compressor unit cover.
3.Noting their fitted position, disconnect pipes
from air valves and discard 'O' rings.
4.Disconnect air valve multiplugs.
5.Remove 2 bolts securing air valves and
remove air valves. Refit
1.Position air valves and fit and tighten bolts.
2.Connect air valve multiplugs.
3.Connect air valve pipes.
4.Ensure pipes are located in cut outs in casing.
5.Position air compressor unit cover and lock
fasteners.
6.Repressurise SLS air system using TestBook.
WARNING: Eye protection must be worn
during the repressurisation procedure.

REAR SUSPENSION
REPAIRS 64-39
Actuator - rear - ACE
$% 64.60.40
CAUTION: The ACE hydraulic system is
extremely sensitive to the ingress of dirt or
debris. The smallest amount could render the
system unserviceable. It is imperative that the
following precautions are taken.
lACE components are thoroughly cleaned
externally before work commences;
lall opened pipe and module ports are
capped immediately;
lall fluid is stored in and administered
through clean containers.
Models with SLS:
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Raise vehicle on ramp.
2.Remove nuts securing anti-roll bar links to
axle. Release links from axle.
3.Pull torsion bar down for access to actuator. 4.Remove nut securing anti-roll bar link to long
arm and remove link.
5.Position container to collect fluid spillage.
6.Remove cap nuts securing fluid pipes to
actuator. Disconnect pipes and remove and
discard sealing washers.
CAUTION: Always fit plugs to open
connections to prevent contamination.

REAR SUSPENSION
REPAIRS 64-41
Bushes - rear long arm - ACE
$% 64.60.46
CAUTION: The ACE hydraulic system is
extremely sensitive to the ingress of dirt or
debris. The smallest amount could render the
system unserviceable. It is imperative that the
following precautions are taken.
lACE components are thoroughly cleaned
externally before work commences;
lall opened pipe and module ports are
capped immediately;
lall fluid is stored in and administered
through clean containers.
Models with SLS:
WARNING: Ensure the air suspension system is
made safe before commencing work. Otherwise
the chassis may lower onto the bump stops
during repair.
Remove
1.Raise vehicle on ramp.
2.Remove nuts securing anti-roll bar links to axle.
Release links from axle.
3.Pull torsion bar down for access to actuator.4.Remove securing nuts and remove anti-roll bar
links from torsion bar.
5.Position container to collect fluid spillage.
6.Remove cap nuts securing fluid pipes to
actuator. Disconnect pipes and remove and
discard sealing washers.
CAUTION: Always fit plugs to open
connections to prevent contamination.
7.With assistance, remove bolts securing torsion
bar clamps. Remove clamps and remove
torsion bar and actuator.

BRAKES
DESCRIPTION AND OPERATION 70-5
Description
General
The brakes consist of front and rear disc brakes operated by a diagonally split, dual circuit hydraulic system with
vacuum servo power assistance. The system incorporates the following control functions as standard on all models:
lAnti-lock Brakes (ABS), to prevent road wheels locking during brake application.
lElectronic Brake Distribution (EBD), to control distribution of hydraulic pressure between front and rear axles.
Replaces mechanical pressure limiting valve of previous systems.
lElectronic Traction Control (ETC), to maintain even torque distribution to the road wheels.
lHill Descent Control (HDC), to provide controlled descent ability in off road conditions.
Hydraulic system schematic
1Master cylinder/brake servo assembly
2Brake pedal
3ABS modulator
4Rear brake5Front brake
6Hydraulic circuit
aPrimary
bSecondary
For normal brake operation, brake pedal movement is assisted by the brake servo assembly and transmitted to the
master cylinder assembly. The master cylinder assembly converts brake pedal movement to hydraulic pressure.
Primary and secondary brake pipe circuits supply the hydraulic pressure to the brakes via the ABS modulator: the
primary circuit supplies the front left and rear right brakes; the secondary circuit supplies the front right and rear left
brakes. Vacuum for the brake servo assembly is obtained from the engine inlet manifold (V8 models) or a vacuum
pump (diesel models), through a vacuum line and non return valve. To reduce operating noise, sleeving is installed
on some of the brake pipes in the engine compartment and the pipes are located in sprung pipe clips.
For all control functions, the ABS modulator regulates the hydraulic pressure to the brakes to control the speed of all
four wheels, either individually or in axle pairs. Operation of the ABS modulator is controlled by the Self Levelling and
Anti-lock Braking Systems (SLABS) ECU. The SLABS ECU also operates warning indications in the instrument pack
to provide the driver with status information on each function.