ABS LAND ROVER DISCOVERY 2002 Manual Online

FRONT SUSPENSION
REPAIRS 60-35
Wheel hub
$% 60.25.01
Remove
1.Release ABS sensor harness grommet from
inner wing valance and disconnect multiplug.
2.Raise front of vehicle.
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.Pull ABS sensor harness through aperture into
wheel arch.
5.Release harness from brackets on inner wing
valance, suspension turret and front hub.
6.Release stake from drive shaft nut.
7.With assistance, remove drive shaft nut.
Discard the nut.
8.Remove front brake disc.

+ BRAKES, REPAIRS, Brake disc -
front.

FRONT SUSPENSION
60-36 REPAIRS
9.Remove 4 bolts securing wheel hub to steering
knuckle.
10.Release wheel hub from steering knuckle, then
remove wheel hub and drive shaft assembly
from axle.
CAUTION: Do NOT remove the ABS sensor
from the hub. The hub and the sensor are
supplied as an assembly.
11.Position the wheel hub and drive shaft on a
press, place supports beneath the wheel studs
and press the drive shaft from the wheel hub.
12.Remove drive shaft oil seal from axle casing. Refit
1.Clean drive shaft oil seal recess, drive shaft
splines, oil seal running surface, wheel hub
and steering knuckle mating faces, ABS
sensor and sensor recess.
2.Lubricate lip of new drive shaft oil seal and
running surface on drive shaft with clean
differential oil.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Lubrication.
3.Use tool LRT-51-012 to fit new drive shaft oil
seal to axle casing.
4.Fit drive shaft to axle casing.
5.Apply anti-seize compound to wheel hub and
steering knuckle mating face.
M51 0057

FRONT SUSPENSION
REPAIRS 60-37
6.Apply a 3 mm (0.125 in) wide bead of Loctite
640 around drive shaft circumference, as
illustrated.
7.Ensure ABS harness is located in cut out in
steering knuckle.
8.Fit wheel hub to drive shaft and align steering
knuckle. The Loctite will smear along the length
of the splines as the wheel hub is fitted to the
drive shaft.
9.Fit wheel hub bolts and tighten to 100 Nm (74
lbf.ft).
10.Fit new drive shaft nut and lightly tighten.
11.Fit front brake disc.

+ BRAKES, REPAIRS, Brake disc -
front.
12.With assistance, final tighten drive shaft nut to
490 Nm (360 lbf.ft). Stake drive shaft nut. The
drive shaft nut must be tightened before
Loctite has cured.
13.Secure ABS sensor harness to brackets and
secure grommet to inner wing.
14.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
15.Remove stand(s) and lower vehicle.
16.Connect ABS sensor multiplug.
Damper - front
$% 60.30.02
Remove
1.Raise front 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.
3. RH damper: Release coolant reservoir and
position aside.
4.Loosen through bolt securing damper to turret.
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.
M51 0058

FRONT SUSPENSION
60-40 REPAIRS
Refit
1.Clean bush locations in radius arm.
2.Press bushes into radius arm:
lUse LRT-60-011/1, LRT-60-011/2 and
LRT-60-011/3 to fit bush at rear of radius
arm.
3.Position radius arm to vehicle. Fit securing
bolts and nuts but do not tighten at this stage.
4.Fit track rod to steering knuckle. Fit and tighten
nut to 125 Nm (92 lbf.ft).
5.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
6.Remove stand(s) and lower vehicle.
7.Tighten radius arm nuts and bolts to 230 Nm
(170 lbf.ft).
CAUTION: Nuts and bolts must be tightened
with weight of vehicle on suspension.
ECU - ACE
$% 60.60.01
Remove
1.Remove BCU.

+ BODY CONTROL UNIT, REPAIRS,
Body control unit (BCU).
2.Remove 5 multiplugs from SLABS ECU.
3.Remove multiplug from ACE ECU.
4.Remove lower nut and loosen upper nut
securing SLABS and ACE ECU bracket to
body.
5.Remove ECU's and bracket assembly.

FRONT SUSPENSION
REPAIRS 60-41
6.Remove 3 nuts securing ACE ECU and remove
ACE ECU.
Refit
1.Fit ACE ECU to bracket and secure with nuts.
2.Fit ECU's and bracket assembly to body and
secure with nuts.
3.Connect multiplugs to ACE ECU and SLABS
ECU.
4.Fit BCU.

+ BODY CONTROL UNIT, REPAIRS,
Body control unit (BCU).
5.If a replacement ACE ECU has been fitted, use
TestBook to calibrate ACE system.
Accelerometer - ACE - upper
$% 60.60.02
CAUTION: The accelerometer is an extremely
delicate component and can easily be rendered
unserviceable. Never use an accelerometer
which has been dropped or subjected to
mistreatment of any type.
Remove
1.Remove front stowage pocket.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Stowage pocket - front.
2.Disconnect multiplug from accelerometer.
3.Use LRT-60-014A to release clip and remove
accelerometer.
Refit
1.Using LRT-60-014A, fit accelerometer fully into
clip.
2.Connect accelerometer multiplug.
3.Fit front stowage pocket.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Stowage pocket - front.
4.If a replacement accelerometer has been fitted,
use TestBook to calibrate ACE system.

REAR SUSPENSION
DESCRIPTION AND OPERATION 64-9
DESCRIPTION AND OPERAT ION
SLS component layout
RH drive shown, LH drive similar
1Off-road mode switch
2SLS warning lamp
3Instrument pack
4Off-road mode warning lamp
5RH Height sensor
6RH Air spring
7Air inlet filter
8LH Air spring
9LH Height sensor
10Air supply unit
11SLABS ECU

REAR SUSPENSION
DESCRIPTION AND OPERATION 64-11
1Battery supply (via SLABS relay)
2Ignition supply
3RH height sensor
4LH height sensor
5Off-road mode warning lamp
6Audible warning speaker
7Instrument pack
8SLS warning lamp
9Fusible link 9
10SLS relay
11Air supply unit12RH air valve
13LH air valve
14Exhaust valve
15Diagnostic socket
16Off-road mode switch
17SLS remote handset
18Body Control Unit (BCU)
19Door switches
20SLABS ECU
21Engine Control Module (ECM)

REAR SUSPENSION
64-12 DESCRIPTION AND OPERATION
Description - SLS
General
The Self Levelling Suspension (SLS) system is an optional fitment and comprises an Electronic Control Unit (ECU),
air supply unit, two air springs and two height sensors. The SLS system only operates on the rear suspension and is
designed to keep the vehicle level to compensate for uneven loads or when towing. The system controls the gap
between the chassis and the rear axle to a tolerance of
± 0.5 mm (0.02 in). The ride height of the rear of the vehicle
can be controlled in three modes of operation; normal ride height, Off-Road Mode (ORM) and extended mode. A
transportation mode, initiated using TestBook, is also available for moving the vehicle on a trailer.
The system is controlled electronically by an ECU which is shared with the ABS system and known as the Self
Levelling and Anti-Lock Braking System (SLABS) ECU. The system operates by using an air supply unit to inflate or
deflate the air springs to maintain a constant ride height.
An accessory remote handset is available to remotely operate the SLS system to allow easier connection and
disconnection of trailers.
Two SLS system warning lamps are located in the instrument pack. The warning lamp in the bottom left corner of the
instrument pack is the SLS warning lamp. If a fault is detected in the system, the warning lamp will illuminate
continuously in an amber colour. The warning lamp also flashes in an amber colour when the remote handset is being
used. The second warning lamp, located in the top right of the instrument pack is the ORM warning lamp. When ORM
is selected the warning lamp is continuously illuminated in an amber colour. When the SLS is between standard ride
height and ORM or in extended mode, the warning lamp will flash. Standard ride height, measured between the tip of
the axle bump stop rubber and the axle, is 61.5 mm (2.42 in). ORM ride height, measured between the tip of axle
bump stop and the axle, is 100 mm (3.93 in).
A switch is located in the group of six switches on the fascia and is used to select the ORM. The switch is non-latching
and must be depressed for a minimum of 0.5 seconds to signal the ECU that ORM has been requested.

REAR SUSPENSION
64-14 DESCRIPTION AND OPERATION
The air supply unit comprises a 12 V electric motor, a compressor and air dryer unit, a pressure limiting valve, an
exhaust valve and two air supply control valves. The exhaust and control valves are solenoid operated responding to
signals from the SLABS ECU. The electric motor, compressor, air dryer and pressure limiting and exhaust valve are
mounted on flexible rubber mountings to reduce operating noise.
The electric motor drives a crank with an eccentric pin to which a connecting rod is attached. The connecting rod has
a piston which fits in the bore of the compressor. Operation of the motor rotates the crank, moving the piston in the
bore of the compressor.
The compressor is attached with Allen bolts to the motor housing and sealed with an O-ring. Attached to the
compressor is the air dryer which contains a silicate box for removing moisture from the compressed air. Air supplied
to inflate the air springs passes through the air dryer. When the air springs are deflated, the exhaust air also passes
through the air dryer, removing the moisture from the unit and expelling it to atmosphere.
Attached to end of the air dryer unit is the pressure limiting valve. The valve protects the air springs from over inflation.
The pressure limiting valve also operates when the exhaust valve is opened. The valve is pneumatically operated,
responding to air pressure applied to it.
The exhaust valve is also located with the pressure limiting valve. The exhaust valve is solenoid operated by the ECU
and directs air from the air springs and control valves to atmosphere when required.
The two air control valves for the LH and RH air springs are located at the forward end of the housing. Each valve is
connected to the compressor/air dryer unit through a shared single pipe which directs air to and from the air springs.
Each control valve is individually operated by the ECU.
All air connections to and from the air supply unit are made through the SLS air harness which is located along the
left hand chassis longitudinal.
If faults occur with the air supply unit, fault codes are stored in the SLABS ECU. These fault codes cover the
compressor power supply and the LH and RH air control valves and the exhaust valve. The current and past fault
codes can be retrieved with TestBook. TestBook can also be used to operate the compressor and the valves for
diagnostic purposes.
Air intake filter
The air intake filter is located in the left hand 'E' post, behind the tail lamp assembly. The filter comprises a plastic
moulded housing which contains two filters of differing density to remove particulate matter from the air drawn in by
the compressor. The air intake filter has a pipe which is connected to the SLS air harness by a quick release
connector. The air intake filter must be replaced as an assembly.
Air intake/Exhaust silencer
The air intake/exhaust silencer is located on the outside of the left hand chassis longitudinal, behind the air supply
unit. The silencer is an integral part of the SLS air harness and cannot be serviced individually.
The intake and exhaust air to and from the compressor passes through the silencer. The plastic moulded silencer has
two chambers. One chamber reduces system exhaust noise and the other dampens intake air pulses produced by
the compressor.

REAR SUSPENSION
DESCRIPTION AND OPERATION 64-15
Height sensors
1Spacer
2Link end
3Link
4Link end
5Arm
6Sensor body
Two height sensors are located on the outside of each chassis longitudinal forward of the rear axle. Each sensor body
is attached to a fabricated bracket and secured with two screws. The sensor is attached to the top of each radius arm
by an arm, a link and two link ends. The link ends allow articulation of the arm to allow for suspension travel. The lower
link arm is attached to a lug of the top of the radius arm and is secured with a bolt and locknut.
The sensor body and arm are manufactured from moulded nylon. The two link ends are made from natural rubber
and the link is made from mild steel. The rubber link ends allow flexibility of the arm and resistance to damage.
Each sensor is connected to the main chassis harness by a multiplug. The three pin multiplug provides an earth, a 5
V supply voltage and an output signal voltage to the SLABS ECU.
Each sensor operates on the Hall effect principle. A magnet is attached to the shaft and rotates with movement of the
arm. The magnetic flux generated acts on a Hall effect sensor and depending on its position varies the current across
the sensor. This current is measured and amplified and passed to the SLABS ECU as a linear output voltage signal,
which varies depending on the angular position of the sensor. The signal information is processed and the ECU can
determine the vehicle height.
When the sensors are replaced or removed for any reason, a calibration procedure is required to recalibrate the
sensors and the SLABS ECU. The calibration procedure requires the use of TestBook and calibration blocks to set
the axle to chassis height to a known value.
If faults occur with the height sensors, fault codes are stored in the SLABS ECU. The current and past fault codes can
be retrieved with TestBook.