steering wheel LAND ROVER DISCOVERY 1999 Repair Manual
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 1999, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 1999Pages: 1529, PDF Size: 34.8 MB
Page 783 of 1529

FRONT SUSPENSION
60-38 REPAIRS
10.Using LRT-60-011/1 and LRT-60-011/2 press
out bush from rear end of radius arm.
11.Using a suitable piece of tubing, press out
bushes from axle end of radius arm.Refit
1.Clean and lubricate bush and radius arm
mating faces.
2.Using LRT-60-011/1,LRT-60-011/2 and LRT-
60-011/3, press bush into rear end of radius
arm.
3.Using a suitable piece of tubing press front
radius arm bush into radius arm.
4.Repeat above operation for remaining bush.
5.Position radius arm to vehicle and fit securing
nuts and bolts, do not tighten at this stage.
CAUTION: Nuts and bolts must be tightened
with weight of vehicle on suspension.
6.Fit cable tie to secure axle breather.
7.Fit track rod to steering knuckle and secure with
nut, tighten to 125 Nm (92 lbf.ft).
8.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
9.Remove stand(s) and lower vehicle.
10.Tighten radius arm nuts and bolts to 230 Nm
(170 lbf.ft).
Page 872 of 1529

BRAKES
DESCRIPTION AND OPERATION 70-19
ABS sensors
The ABS sensors supply the SLABS ECU with a sinusoidal speed signal from each wheel. An inductive sensor,
installed in the hub bearing of each wheel, senses off a 60 tooth exciter ring integrated into the inner race of the hub
bearing. Each ABS sensor has a fly-lead connecting it to the vehicle wiring.
HDC switch
The HDC switch is a latching push switch installed on the fascia, in the switchpack inboard of the steering wheel.
When pushed in, the switch connects an ignition supply to the SLABS ECU to initiate HDC.
Warning indications
The SLABS ECU operates audible and visual warnings to convey brake system status.
Audible warning
A repetitive chime, at a frequency of 2 Hz, draws attention to warning lamp indications. The chime is produced on the
speaker in the instrument pack.
Warning lamps
1ABS warning lamp
2HDC fault warning lamp
3ETC warning lamp4HDC information warning lamp
5Brake warning lamp (all except NAS)
6Brake warning lamp (NAS only)
The following brake system warning lamps can be found in the instrument pack:
lA red brake graphic (all except NAS vehicles) or red BRAKE legend (NAS vehicles), to warn of low brake fluid
level, handbrake on and brake control system failure affecting EBD.
lAn amber ABS graphic, to warn of brake control system failure affecting the ABS function.
lAn amber TC graphic, to warn of brake control system failure affecting the ETC function.
lTwo inclined vehicle graphics, one amber (fault) and one green (information), to indicate operating status of HDC
and to warn of brake control system failure affecting the HDC function.
Each warning lamp is illuminated by a separate LED. The ABS, brake and ETC warning lamps are continuously on
while illuminated; the two HDC warning lamps are either continuously on or flash at a frequency of 2 Hz while
illuminated.
Page 873 of 1529

BRAKES
70-20 DESCRIPTION AND OPERATION
Operation
Refer to illustration.
+ BRAKES, DESCRIPTION AND OPERATION, Brake system control diagram.
When the ignition is switched on, the SLABS ECU performs a check of the brake related warning lamps as part of the
power up procedure. The warning lamps are illuminated for approximately 3 seconds and then extinguished. If a fault
warning lamp remains illuminated after the lamp check, a fault has been detected and repair action is required.
ABS
The ABS function prevents the road wheels locking during brake application, thus maintaining vehicle stability even
under emergency conditions.
WARNING: ABS is an aid to retaining steering control and stability while braking:
lABS cannot defy the natural laws of physics acting on the vehicle.
lABS will not prevent accidents resulting from excessive cornering speeds, following another vehicle too
closely, aquaplaning, etc.
lThe additional control provided by ABS must never be exploited in a dangerous or reckless manner
which could jeopardise the safety of driver or other road users.
lThe fitting of ABS does not imply that the vehicle will always stop in a shorter distance.
NOTE: During normal braking the feel of the brake pedal on vehicles equipped with ABS will be the same as that on
non ABS vehicles. During anti-lock braking operation the driver will experience feedback in the form of a pulsating
brake pedal and solenoid/pump motor noise from the ABS modulator.
The anti-lock braking function is automatically enabled whenever the ABS modulator is in the normal braking mode.
While the anti-lock braking function is enabled, if the SLABS ECU detects a wheel decelerating faster than the
average and at the calibrated wheel slip limit for ABS operation, it operates the ABS modulator in the ABS braking
mode for the affected wheel.
EBD
The EBD function optimises the distribution of hydraulic pressure between the front and rear axles, under all vehicle
load configurations and road conditions, to maintain vehicle stability during braking. EBD operates in forward and
reverse and is automatically enabled whenever the ABS modulator is in the normal braking mode at vehicle
deceleration rates of 0.3 g and above (i.e. medium to high brake pedal loads). EBD operation is similar to that of ABS,
but is calibrated to intervene at lower wheel slip limits and operates the brakes in axle pairs instead of individually.
During braking, if the SLABS ECU detects the wheels of one axle going slower than those of the other axle, i.e. a
potential wheel slip situation, it signals the ABS modulator to close the inlet solenoid valve for the brakes of the slower
wheels. This prevents any further increase in hydraulic pressure to those brakes, while allowing the hydraulic pressure
to the brakes on the other axle to increase and so maximise the overall braking effort. If the wheel speeds of the axle
being subjected to EBD control return within the calibrated wheel slip limits, the SLABS ECU signals a stepped
opening of the inlet solenoid valves, which allows a progressive increase of hydraulic pressure to the related brakes.
Operation of EBD is detectable from a stiffening of brake pedal movement as the inlet solenoid valves close and a
slight pulsing of the brake pedal as the inlet solenoid valves open. EBD operation ceases immediately the brake pedal
is released.
The wheel slip limit for EBD operation varies with vehicle speed. During normal operation, the inlet solenoid valves
always operate in axle pairs, with only one axle pair closed at any one time. Since the most lightly loaded wheel during
a braking manoeuvre will usually be the first to reach the slip limit, under most vehicle load configurations and road
conditions EBD control occurs on the trailing axle. However, EBD control can occur on the leading axle or switch
between axles during the braking manoeuvre.
Page 907 of 1529

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.
Page 925 of 1529

RESTRAINT SYSTEMS
75-22 REPAIRS
Airbag module - drivers
$% 76.74.01
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 2 Torx bolts securing air bag module
to steering wheel.
3.Release air bag module from steering wheel.
CAUTION: Do not allow the air bag module
to hang by the air bag harness.
4.Disconnect multiplug from air bag module. 5.Remove air bag module.
WARNING: Store the airbag module with the
deployment side uppermost. If it is stored
deployment side down, accidental
deployment will propel the airbag module
with enough force to cause serious injury.
WARNING: Store the airbag module or seat
belt pre-tensioner in a designated storage
area. If there is no designated storage area
available, store in the locked luggage
compartment/loadspace of the vehicle and
inform the workshop supervisor.
Refit
NOTE: If the airbag module is to be replaced,
the bar code of the new module must be
recorded.
1.Position air bag module and connect multiplug.
2.Fit air bag module to steering wheel and tighten
Torx bolts to 9 Nm (7 lbf.ft).
3.Connect battery leads, earth lead last.
Page 928 of 1529

RESTRAINT SYSTEMS
REPAIRS 75-25
Air bag - steering wheel - deployment -
off vehicle
$% 76.74.16
These guidelines are written to aid authorised
personnel to carry out the safe disposal of air bag
modules when removed from the vehicle.
Deploy
It is imperative that before any work is
undertaken on the SRS system, the
appropriate information is read thoroughly.
1.Check condition of deployment tool LRT-86-
003 and associated fly leads.
2.Position LRT-86-007/02 in vice, ensuring that
vice jaws grip tool above the bottom flange to
prevent possibility of tool being forced upwards
during detonation. Tighten vice.
3.Fit and secure 2 off LRT-86-007/05 to LRT-86-
007/02.4.Fit and secure air bag to LRT-86-007/05.
5.Connect deployment tool fly lead LRT-86-003/
08 to air bag.
6.Connect deployment tool LRT-86-003 to
deployment tool fly lead LRT-86-003/08.
7.Connect deployment tool LRT-86-003 to
battery.
WARNING: Ensure all personnel are at least
15 metres (50 feet) away from the air bag
module.
8.Press deployment tool operating button to
deploy air bag module.
9.Disconnect deployment tool from battery.
WARNING: During deployment parts of the
air bag module become hot enough to burn
you. Wait 30 minutes after deployment
before touching the air bag module.
10.Disconnect deployment tool fly lead from air
bag.
11.Remove air bag module from holding tools and
place in a sealed bag, ready for disposal.
NOTE: Do not transport deployed SRS
components in the vehicle passenger
compartment.
12.Wipe down holding tools with a damp cloth and
remove from vice.
13.Transport deployed air bag module to
designated area for incineration.
14. Do not re-use or salvage any parts of the
SRS system.
Page 932 of 1529

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.
Page 975 of 1529

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.
Page 978 of 1529

INTERIOR TRIM COMPONENTS
REPAIRS 76-3-13
11.Fit instrument pack to fascia and secure with
screws.
12.Position instrument cowl and connect
multiplugs to switches.
13.Fit cowl to clips on fascia and secure with
screws.
14.Fit fascia access panel.
+ INTERIOR TRIM COMPONENTS,
REPAIRS, Panel - fascia access - driver's
side.
15.Fit fascia lower closing panels and secure with
clips.
16.Fit fascia mats.
17.Fit 'A' post trim panels.
18.Fit 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.
19.Fit steering column nacelle.
+ STEERING, REPAIRS, Nacelle -
steering column.
20.Fit steering wheel.
+ STEERING, REPAIRS, Steering
wheel.
21.Fit radio cassette player.
+ IN CAR ENTERTAINMENT,
REPAIRS, Radio.
22.Connect battery.
Page 1243 of 1529

WIPERS AND WASHERS
84-8 DESCRIPTION AND OPERATION
Description
General
All markets have a common wiper system with headlamp powerwash as an option.
The wipers system comprises two front wipers and one rear wiper which are powered by electric motors. A washer
reservoir is located in the front left hand wheel arch and is fitted with two electric pumps. Each pump supplies washer
fluid to either the front or rear screens. On certain models, a third pump can be fitted to operate a headlamp power
wash function. Operation of the front and rear wipers and washers is controlled by the driver using switches located
on a steering column stalk and push button switches on the fascia.
Control of the wipers and washers is achieved by the following components:
lBCU.
lIDM.
lFront wiper relay.
lFront wash/ wipe switch.
lVariable delay switch.
lFront wiper motor assembly.
lFront washer pump motor.
lRear wiper relay.
lRear wiper switch.
lRear washer switch.
lRear wiper motor.
lRear washer pump motor.
Both the Body Control Unit (BCU) and the Intelligent Driver Module (IDM) control the wiper system. The BCU controls
the time delay function of the wiper system and is located below and behind the passenger glovebox. During engine
cranking the BCU prevents wiper functions. Two relays are located in the passenger compartment fusebox. The
relays control the delay operation of the front and rear wipers. The relays are an integral part of the fusebox and
cannot be renewed separately.
Power for the wiper system is supplied by the IDM, which is integral with the passenger fusebox and cannot be
renewed as a component. A serial communication link allows communication between the IDM and the BCU.
The system has diagnostic capabilities through TestBook.
Front wipers
The two front windscreen wipers are operated by a linkage assembly and an electric motor located under the plenum
grill below the windscreen. The linkage and motor assembly is handed for left and right hand drive vehicles. The motor
is an integral part of the linkage and cannot be replaced separately.
The linkage comprises a pressed steel mounting plate which provides for the attachment of a wheel box at each end.
The mounting plate is secured to the bulkhead with flanged nuts which attach to a stud plate located behind the
bulkhead. A link arm is attached to each wheel box by a short link and secured with circlips. The link arm has an
attachment hole centrally located along its length for the electric motor drive link.
The electric motor is mounted in a recess in the bulkhead below a sealed cover plate. The drive spindle of the motor
protrudes through the cover plate and is fitted with a link. The link is attached to a tapered spline on the motor spindle
and is secured with a lock washer and nut. The opposite end of the link is attached to the central attachment point on
the link arm and secured with a circlip.
Each wheel box has a taper splined shaft which allows for the attachment of the wiper arm which is secured with a
washer and nut. The shaft of each wheel box is passed through a rubber sealed aperture in the plenum. The wiper
arm attachment to the splined shaft has a pivot to which the remainder of the arm is attached. The two parts of the
arm are connected by a spring which controls the pressure of the blade on the screen to a predetermined amount.
The wiper blades are attached to the wiper arms with a clips that allow the blade to pivot. Each wiper blade comprises
a number of levers and yokes to which the rubber wiper is attached. The levers and yokes ensure that the pressure
applied by the arm spring is distributed evenly along the full length of the blade. The rubber wiper is held in the yokes
by a pair of stainless steel strips which also contribute to the even distribution of spring pressure along the blade. The
driver's side wiper blade is fitted with an aerofoil which presses the blade onto the screen at high speed. This prevents
the blade from lifting off the screen and maintains the wiping performance.