steering wheel LAND ROVER DISCOVERY 1999 Repair Manual

WIPERS AND WASHERS
DESCRIPTION AND OPERATION 84-13
Rear wiper motor
The DC motor contains two permanent magnets and a park switch. An earth braid attached between the motor casing
and the brush pack is utilised to minimise radio interference during wiper functions.
The rear wiper switch provides an earth signal to the BCU, which determines the delay interval, if appropriate. The
BCU then signals the IDM to activate the rear wiper motor relay, which provides power to the rear wiper motor.
To allow the rear wiper to park when the rear wiper is switched off, power flows through the park switch until a cam
in the wiper motor assembly breaks the contact of the park switch. Triggering the park switch grounds the positive
side of the wiper motor causing it to stop abruptly
Washers
The washer system comprises a reservoir, washer pumps, hoses and washer jets. The front washers are controlled
from a stalk switch on the steering column and the rear washers are operated by a non-latching pushbutton switch on
the fascia adjacent to the instrument pack.
Reservoir
The reservoir is located behind the front bumper in the inner wheel arch and has a capacity of 6.0 litres (12.5 US pints).
A filler neck tube is connected to the reservoir with a seal and extends into the engine compartment on the front left
hand side. The filler neck tube contains a removable filter to prevent particle contamination and a yellow float to show
reservoir contents. The washer filler neck tube is sealed with a cap which is coloured blue for identification.
Two electric washer pumps are located on the rear face of the reservoir and supply washer fluid to the front
windscreen and the tail door window. Each pump is sealed to the reservoir with a rubber sealing grommet.
On vehicles with headlamp powerwash fitted, a third pump is fitted with a sealing grommet to the front face of the
reservoir.
The reservoir and filler neck tube are manufactured from moulded opaque nylon. The reservoir has moulded lugs for
attachment to the vehicle body. A bracket is attached to the top of the filler neck tube and locates in a hole in the body
to secure the top of the tube.
Front screen washer jets
Two washer jets for the front windscreen are fitted to the top surface of the bonnet and held in place with plastic clips.
Each washer jet is connected via a hose to an in-line valve. The in-line valve prevents the washer fluid draining back
to the reservoir and ensures that the washers operate immediately the washer pump is operated. From each in-line
valve the washers are connected via a short hose to a 'T' connector. From the 'T' connector a single hose connects
to the outlet of the front washer pump. Each jet has two jets which can be adjusted to allow full fluid coverage of the
windscreen.

BODY CONTROL UNIT
86-3-14 DESCRIPTION AND OPERATION
Central Door Locking (CDL)
The BCU carries out the logic control operation for CDL. A CDL switch is mounted on the fascia panel and has two
inputs to the BCU, one for lock and one for unlock.
Door locking and unlocking can be performed using the remote transmitter in the keys and the receiver unit located
above the vehicle's headlining, behind the rear sunroof aperture. The receiver detects the signals sent from the
remote transmitter and sends a decoded signal to the BCU for processing.
Four methods of door locking are available:
lRemote handset locking.
lVehicle key locking.
lCDL switch locking.
lSpeed related locking.
Two security levels of door locking are available, CDL and Superlocking. The anti-theft alarm system works in
conjunction with the CDL system.
Electric windows and sunroof
The BCU controls the logical operations and the timing periods for the electric front windows. The rear windows are
hard-wired and the two electric sunroofs are controlled by a dedicated ECU which is enabled by the BCU.
The front windows are electrically operated using two rocker switches located in the centre console. Electric motors
are located in each of the front doors.
The rear windows are enabled by the IDM controlling the operation of the rear window relay located in the passenger
compartment fuse box.
Wipers and washers
The wiper and washer functions are controlled by the BCU and the IDM.
The front wipers and washers are operated from the switch stalk located on the right hand side of the steering column
and only operate when the ignition switch is in position I or II. The front wipers are operated by a motor located below
the windscreen plenum.

+ WIPERS AND WASHERS, DESCRIPTION AND OPERATION, Description.
The BCU controls the wiper motor frequency of operation via the IDM when intermittent wipe or wash is selected. The
front intermittent wipe option features five different intermittent delay periods. The shortest delay period is 3 seconds
and this is increased by 2 second increments up to a maximum delay of 11 seconds. The desired delay period for the
front wipers is set by the position of the rotary switch located on the wiper column stalk.
The rear wiper switch is located on the instrument pack cowl and is latched when pressed. The rear wiper electric
motor is located in the tail door. The rear wiper operation is controlled according to a programmed strategy via the
BCU and the IDM. The BCU also checks for a signal from either the reverse lamp switch located in the vehicle gearbox
(manual gearbox models) or the gear position switch (automatic gearbox models) for operating the rear wipers when
the vehicle is in reverse. The rear wiper and washer only operate when the ignition switch is in position II.
The front and rear washer pumps and the headlamp powerwash (where fitted) are also controlled through the BCU.
The washers are operated from electric pumps attached to the washer reservoir located in the left hand wheel arch.
The front wash switch is located on the wiper column stalk and is pulled towards the steering wheel to select the
washer function. When the front washers are operated, the wipers are also activated for three full cycles. The rear
wash switch is located on the instrument pack cowl. The BCU programme can be configured in one of two modes of
operation:
lNo wiper operation when the wash switch is pressed.
lWiper action after an initial delay of 400 ms.
Headlamp wash is activated by the BCU via the IDM and operates when the headlamps are on and the front washers
function is selected.

ALARM SYSTEM AND HORN
REPAIR 86-4-25
REPAIR
Switch - central door locking
$% 86.26.30
Remove
1.Carefully remove clock assembly from louvre
panel.
2.Disconnect multiplug from door lock switch.
3.Remove door lock switch from clock.
Refit
1.Fit door lock switch to clock assembly.
2.Connect multiplug to door lock switch.
3.Position clock assembly and push to secure in
position.
Switches - horn
$% 86.30.01
Remove
WARNING: It is imperative that before any
work is undertaken on the SRS system the
appropriate information is read thoroughly.
1.Disconnect both battery leads, negative lead
first, and wait 10 minutes.
2.Remove driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.
3.Release horn switch multiplugs and leads from
steering wheel base.
4.Disconnect horn switch multiplugs from
harness.
5.Disconnect horn switch multiplug from rotary
coupler harness.
6.Remove screw securing earth leads to steering
wheel.
7.Using a broad round edged tool, carefully prise
horn switches from steering wheel.
Refit
1.Fit to steering wheel and connect multiplugs.
2.Fit earth leads and secure with screw.
3.Secure leads and multiplugs to base of steering
wheel.
4.Fit driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.

IN CAR ENTERTAINMENT
86-6-4 DESCRIPTION AND OPERATION
Description
General
The in car entertainment (ICE) system allows the driver and passengers to listen to audio output from the speakers
or optional headphones inside the vehicle. Buttons or knobs on the radio cassette allow changes of levels or
selections during the various modes of operation. The system can be controlled from the fascia mounted radio
cassette, or optional remote control switches on the left hand side of the steering wheel. High line systems may also
have rear headphone amplifiers that have some control of the system via the radio cassette player.
One or two amplified aerials located in the rear side windows send radio signals to the radio cassette player. On high
line systems a power amplifier and a CD-autochanger may be located under the front seats. Speakers are located in
the lower door panels, additional speakers may be located in upper door trim, the A-post and the tail door. A display
screen shows the user the current system status.
The ICE supplied varies with trim level and market. Vehicles may not have all of the speakers, amplified aerials, CD-
autochanger, rear headphone amplifiers or power amplifier.
Base system radio cassette
The base radio cassette has buttons for LD (loudness) AM, FM, EJECT (tape), Reverse, Base/Balance, treble, MAN
forward and reverse. The base radio cassette is located in the center of the fascia and contains the radio and tape
player, four clips (accessible through holes in the front of the unit) secure the unit in the fascia. To remove the unit
the four clips must be released with a special tool. The base system can be controlled from the fascia mounted radio
cassette. A logic control circuit in the radio cassette player controls the operation in the various control modes.
The radio cassette has a display screen, the information shown can be the current radio frequency, tape operating,
bass or loudness settings. Power for the illumination on the radio cassette is supplied from the passenger
compartment fuse box. A main fuse is also located in the connector socket area on the back of the radio cassette.
Security code function
A combination of buttons on the radio cassette are used to input and change security codes. Security codes make the
unit unusable if the unit is disconnected from the vehicle without deactivating the security code. The radio cassette
has an internal memory chip that stores the code information, if the power is removed from the unit the chip will
activate the security code feature. For this reason the security code feature must be deactivated before the unit is
removed or the vehicles battery is disconnected.
Audio functions
The radio cassette has buttons for the following audio functions: LD (loudness), bass/balance, fader, treble and
volume.
Cassette functions
The radio cassette has buttons for the following cassette functions: eject, forward, reverse and tape reversal.
Multi function buttons
The function of presets 1-6 and the MAN button depends on current mode of operation and allows selection of radio
band, radio on, tape track and search/seek functions. The MAN button is mode dependent, when pressed the button
allows manual operation or alternate mode selections such as manual tuning.
Internal memory
An internal memory chip stores the station presets and security code, power is supplied internally to the chip via a
permanent power feed, supplied from the passenger compartment fuse box.

IN CAR ENTERTAINMENT
DESCRIPTION AND OPERATION 86-6-5
Radio cassette player connector pin details.
Connector/Pin
No.Description Input/Output
C0092
1 Rear RH speaker line Output +
2 Rear RH speaker line Output -
3 Front RH speaker line Output +
4 Front RH speaker line Output -
5 Front LH speaker line Output +
6 Front LH speaker line Output -
7 Rear LH speaker line Output +
8 Rear LH speaker line Output -
C0098
1 Telephone mute Input
2 Steering wheel remote radio controls Input
3 Steering wheel remote radio controls Output
4 Permanent battery feed Input
5 System enable Output
6 Illumination Input
7 Auxilary feed Input
8 Earth Input
C0921 (high line systems)
1 Radio headphone left channel Output +
2 Radio headphone right channel Output +
3 Telephone audio Input +
4 Radio headphone left channel Output -
5 Radio headphone right channel Output -
6 Telephone audio Input -

IN CAR ENTERTAINMENT
86-6-6 DESCRIPTION AND OPERATION
Midline system radio cassette
The midline radio cassette is located in the center of the fascia and contains the radio and tape player, four clips
(accessible through holes in the front of the unit) secure the unit. To remove the radio cassette unit the four clips
must be released with a special tool. The midline system can be controlled from the fascia mounted radio cassette,
or from remote radio control switches on the left hand side of the steering wheel. The audio signal can be from the
radio, cassette player or a optional CD-autochanger. A logic control circuit in the radio cassette player controls the
operation in the various control modes.
The radio cassette has a display screen, information shown can include current status, station (radio mode) or
cassette tape track or (optional) CD-autochanger track/disc status. Power for illumination on the radio cassette is
supplied from the passenger compartment fusebox. A main fuse is also located in the connector socket area on the
back of the radio cassette.
Security code function
A combination of buttons on the radio cassette are used to input and change security codes. Security codes make the
unit unusable if the unit is disconnected from the vehicle without deactivating the security code. The radio cassette
has an internal memory chip that stores the information, if the power is removed from the unit the chip will activate the
security code feature. For this reason the security code feature must be deactivated before the unit is removed or the
vehicles battery is disconnected.
Audio functions
A rotary knob allows changes of levels or selections during the various modes of operation, this includes volume,
bass, treble and fader.
Cassette functions
The radio cassette has buttons for the following cassette functions eject, tape, reverse, forward, tape eject/reversal.
Radio functions
The radio cassette has buttons for the selection of AM or FM reception. Selection of the radio station is controlled by
the use of the multi-function buttons on the radio cassette player, the radio headphone amplifiers or the remote radio
controls on the steering wheel.
Traffic information and news function
A traffic information button (TA/NEWS) allows traffic or news information to be selected on the FM waveband only, in
this mode the audio output will mute when traffic or news messages are received. After the traffic or news message
the radio, cassette tape or CD will resume play, the traffic and news information varies with the country of use and
radio band selected.
C0922 (high line systems)
7 Radio headphone active Input
8 I-BUS communications Input/Output
9 Audio amplifier spatial imaging enable Output
10 Radio headphone LH remote control Input
11 Radio headphone RH remote control Input
12 Headphone remote controls feed Output
C1354 (high line systems)
13 CD-autochanger audio left channel Input +
14 CD-autochanger audio right channel Input +
15 CD-autochanger audio earth Output
16 CD-autochanger audio left channel Input -
17 CD-autochanger audio right channel Input -
18 Not Used
19 CD-autochanger I-BUS communications link Input/Output
20 CD-autochanger permanent feed Output

IN CAR ENTERTAINMENT
DESCRIPTION AND OPERATION 86-6-7
Multi function buttons
Rotary controls are located on the front of the radio cassette for adjustment of bass, treble etc, depending on current
mode selected. Operation of presets 1-6 depends on current mode of operation and allows selection of radio band
(Radio mode on) or CD-autochanger disc (in the CD mode). Scan (Mode dependent) manual or automatic selection
of band or track. RND random play, MODE/MUTE (mode dependent) when pressed the button allows manual
operation or alternate mode selections such as manual tuning, compact disk cue/review, tape forward/rewind modes.
Internal memory
An internal memory chip stores the station presets and security code, power is supplied internally to the chip via a
permanent power feed, supplied from the passenger compartment fuse box.
High line system radio cassette
The high line radio cassette is located in the center of the fascia and contains the radio and tape player. Two clips
(accessible through slots in the front of the unit) secure the unit. To remove the radio cassette unit the two clips must
be released with a special tool. The high line system can be controlled from the fascia mounted radio cassette, or from
remote radio control switches on the left hand side of the steering wheel. In vehicles fitted with radio headphone
amplifiers, the rear seat passengers can control their individual audio output using a headphone amplifier control
panel. The audio signal can be from the radio, cassette player or a CD-autochanger. A logic control circuit in the radio
cassette player controls the operation in the various control modes.
The radio cassette has a display screen, information shown includes current status, station (Radio mode) , CD-
autochanger track/disc status or status of headphone amplifier. Power for illumination on the radio cassette is supplied
from the passenger compartment fusebox. A main fuse is also located in the connector socket area on the back of
the radio cassette. When the radio cassette switch is on, power is made available via internal circuits to the radio
headphone amplifiers.
Security code function
A combination of buttons on the radio cassette are used to input and change security codes. Security codes make the
unit unusable if the unit is disconnected from the vehicle without deactivating the security code. The radio cassette
has an internal memory chip that stores the information, if the power is removed from the unit the chip will activate the
security code feature. For this reason the security code feature must be deactivated before the unit is removed or the
vehicles battery is disconnected.
Audio functions
A rotary knob allows changes of levels or selections during the various modes of operation, this includes volume,
bass, treble, fader and spatial on/off.
Cassette functions
The radio cassette has buttons for the following cassette functions; eject, fast forward, rewind and dolby. The dolby
symbol is shown on the dot matrix display screen if dolby mode is selected.
Radio functions
The radio cassette has buttons for the selection of AM or FM reception. Selection of the radio station is controlled by
the use of the multi-function buttons on the radio cassette player, the radio headphone amplifiers or the remote radio
controls on the steering wheel.
CD-autochanger functions
The CD button on the radio cassette player allows selection of the CD-autochanger. CD disc and track selection is
controlled by the use of the multi-function buttons on the radio cassette player, the radio headphone amplifiers or the
remote radio controls on the steering wheel.
Traffic information function
A traffic/news information button (I) allows traffic or news information to be selected on the FM waveband only, in this
mode the radio will mute when traffic or news messages are received. After the traffic or news message the radio,
cassette tape or CD will resume play, the traffic and news information varies with the country of use and radio band
selected.

IN CAR ENTERTAINMENT
DESCRIPTION AND OPERATION 86-6-9
Inputs and outputs
The radio cassette player receives a mute signal from the telephone system if a call is received, when the call finishes
the mute is removed and the system resumes play. Inputs are also received from the steering wheel control system
(mid line and high line sytems). When the system is turned on, the high line systems radio cassette player:
lsends a 'power on enable' to the power amplifier
lsends an 'enable' signal to the radio headphone amplifiers.
On the high line system the radio cassette player also sends and receives signals from the CD-autochanger and rear
headphone amplifiers (if fitted). On high line systems the radio cassette player sends audio signals to the power
amplifier.
Remote radio steering wheel controls (midline and high line systems)
The remote radio control switch is located on the LH side of the steering wheel and is secured with two screws. The
wiring from the remote radio control switch plugs in to a connector that is part of the steering wheel rotary coupler.
Operation of the remote radio control switches allow the driver to control the ICE without releasing the steering wheel.
Volume, mode and selection functions can be carried out using the steering wheel mounted control switches. Control
inputs from the remote radio control switches are sent to the radio cassette player.
C0098
1 Telephone mute Input
2 Steering wheel remote radio controls Input
3 Steering wheel remote radio controls Output
4 Permanent battery feed Input
5 System enable Output
6 Illumination Input
7 Auxilary feed Input
8 Earth Input
C0921 (high line systems)
1 Radio headphone left channel Output +
2 Radio headphone right channel Output +
3 Telephone audio Input +
4 Radio headphone left channel Output -
5 Radio headphone right channel Output -
6 Telephone audio Input -
C0922 (high line systems)
7 Radio headphone active Input
8 I-BUS communications Input/Output
9 Audio amplifier spatial imaging enable Output
10 Radio headphone LH remote control Input
11 Radio headphone RH remote control Input
12 Headphone remote controls feed Output
C1354 (high line systems)
13 CD-autochanger audio left channel Input +
14 CD-autochanger audio right channel Input +
15 CD-autochanger audio earth Output
16 CD-autochanger audio left channel Input -
17 CD-autochanger audio right channel Input -
18 Not Used
19 CD-autochanger I-BUS communications link Input/Output
20 CD-autochanger permanent feed Output

IN CAR ENTERTAINMENT
REPAIRS 86-6-33
Switches - remote control - ICE
$% 86.50.13
Remove
1.Remove the key from the starter switch.
Disconnect both battery leads, negative lead
first. Wait ten minutes before starting work.
2.Remove driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.
3.Release remote control switches multiplug and
leads from steering wheel base.
4.Disconnect remote control switches multiplug
from harness.
5.Remove 2 screws securing remote control
switches to steering wheel base.
6.Release and remove remote control switches
from steering wheel.
Refit
1.Fit remote control switches to steering wheel
and secure with screws.
2.Connect remote control switches multiplug to
harness.
3.Secure leads and multiplug to base of steering
wheel.
4.Fit driver's airbag module.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.
Amplifier - aerial
$% 86.50.29
Remove
1.Remove rear quarter upper trim casing.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - 'D' post.
2.Disconnect coaxial lead and Lucar connector
from amplifier.
3.Disconnect amplifier from aerial.
4.Remove bolt securing amplifier and remove
amplifier.
Refit
1.Position amplifier and secure with bolt.
2.Connect aerial lead, Lucar connector and
coaxial lead.
3.Fit rear quarter upper trim casing.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - 'D' post.

NAVIGATION SYSTEM
DESCRIPTION AND OPERATION 87-1
NAVIGATION SYST EM DESCRIPTION AND OPERAT ION
Harman/Becker Navigation System
Component Location
1GPS antenna and diplexer unit
2Remote control interface unit3Navigation computer
4Steering wheel switches