1999 LAND ROVER DISCOVERY seat adjustment

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-15
Electric seats
The BCU controls the logical operation of the electrically operated front seats. Two modes of operation are available:

+ SEATS, DESCRIPTION AND OPERATION, Description - electric seats.
lElectric seat adjustment is enabled if the ignition is on or the driver's door is opened for a short time period.
lElectric seat adjustment is enabled if the ignition is on and the driver's door is closed.
The seats are operated by four electric motors which control the seat cushion rear up/ down, the seat cushion front
up/ down, seat cushion forward/ rearward and seat squab recline. The electrically powered lumbar adjustment in each
seat is operated by a single motorised air pump and a solenoid located on the seat squab frame. The air pump inflates
a cushion in the seat squab and the solenoid operates a valve to deflate the cushion. The seat squab and cushion
may also contain heater elements to provide heated seat operation.
The switches for electrically operated seats are located either side of the centre console.
Direction indicators and hazard warning lamps
The direction indicator lamps are operated from a three position direction indicator switch on the left hand, steering
column stalk. The BCU only allows the lamps to work as direction indicators when the ignition switch is in position II.
The BCU also controls the lamps to operate as hazard warning lamps and as a visual warning for the anti-theft system,
in which cases all lamps flash simultaneously irrespective of the ignition switch position.
System control of the direction indicators and hazard warning lamps is provided by the BCU operating with the IDM
and two electronic relays located in the passenger compartment fuse box. The IDM and relays are integral parts of
the passenger compartment fuse box and cannot be serviced individually. The serial data bus is used for
communication of status and operation requests between the BCU, IDM and instrument pack.
The hazard warning lamps are operated from a latching pushbutton switch located on the fascia.
All direction indicator/ hazard warning lamp bulbs are rated at 5 Watts.
Headlamps
The BCU contains a feature which allow the vehicle headlamps to be turned on when the remote transmitter is
pressed (courtesy headlamps).
For markets with daylight running lamps, the BCU controls the logical operation of the daylight running lamps. Options
are daylight running lamps are on if the main beam headlamps are off, or the daylight running lamps are on with main
and dipped beam off and the gearbox not in Park.
Front fog lamps
For markets with front fog lamps fitted, the BCU controls the operation of the front fog lamps. Options can be selected
so that the fog lamps will operate with or without the headlamps on main beam.
Instrument pack
The BCU communicates with the instrument pack via a serial data bus.

+ INSTRUMENTS, DESCRIPTION AND OPERATION, Description.
lThe instrument pack provides the BCU and IDM with details of vehicle speed.
lSignals are provided from the IDM to the instrument pack and BCU when the direction indicator lamps are active.
lFor certain markets, the BCU provides a signal to the instrument pack for indicating when the transfer box is in
neutral.
lThe IDM can signal the instrument pack to illuminate a trailer warning lamp. This operates when the IDM senses
that the current drawn by the indicator circuit exceeds a preset threshold.
lThe odometer reading displayed on the instrument pack LCD screen is also stored in non volatile memory in the
BCU. Whenever the ignition is turned from position I to position II, the instrument pack and the BCU compare
their stored values.
lThe gear selector position is displayed on the instrument pack LCD screen under the direction of the BCU.
Starting
The starting system comprises a starter motor and solenoid located at the rear right hand side of the engine. A starter
relay controlled by the BCU is used to supply battery power for starter solenoid operation. The starter motor receives
its feed directly from the battery.

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
86-6-10 DESCRIPTION AND OPERATION
Aerial
On base and midline ICE systems an AM/FM aerial is built-in to the side window glass on the RH side of the vehicle.
An amplifier is located on the frame above the rear side widow behind the rear quarter trim, and is secured (and
earthed) with one bolt. Coaxial leads connect the aerial to the aerial amplifier and radio cassette. Power is supplied
from the auxilary relay in the engine compartment fuse box, through a fuse in the passenger compartment fusebox to
the amplifier.
On high line ICE systems two amplified aerials are built-in to the side window glass of the vehicle. The two aerials are
an AM/FM aerial on the RH side, and an FM aerial on the LH side. The amplifier for each aerial are located on the
frame above each rear side widow behind the rear quarter trim, and are each secured (and earthed) with one bolt.
Amplified aerials improve the reception quality, the FM aerial gives improved reception in areas of poor signal
(diversity) conditions in urban areas. A Power feed from the radio cassette player is connected to the amplified aerials,
power is available when the cassette player is operating. The aerials are connected to the radio cassette player by
two coaxial cables, a small plug connects the FM only aerial, a larger plug connects the AM/FM aerial.
Power amplifier (high line system)
The amplifier is located on a bracket under the LH front seat and is secured with three screws and washers. The
amplifier receives inputs from the radio, radio cassette player or (via the radio cassette player) the CD-autochanger.
Power for the amplifier is supplied from the passenger compartment fuse box. The amplifier will power up when an
enable logic signal is sent from the radio cassette, this signal is sent by the radio cassette when it is turned on.
CD-autochanger (high line system)
A CD-autochanger is located under the RH front seat, the unit is secured to brackets in the floor with four screws and
washers. A tray is used to hold each compact disk (CD), the loaded tray is then inserted in a magazine, the magazine
holds six trays and is then inserted into the CD-autochanger. A sliding cover protects the internal components of the
CD-autochanger from dirt entry through the magazine opening. An eject button located on the front of the CD-
autochanger can be used to release the magazine from the CD-autochanger. The sliding cover has to be opened
manually before the magazine eject button is pressed. The operation of the CD-autochanger is controlled by inputs
from the radio cassette, the control inputs can be from the radio cassette buttons, the remote radio controls or the rear
radio headphone amplifiers if they are fitted. The output from the CD-autochanger are connected to the radio cassette
player. The radio cassette player sends the outputs to the power amplifier. Power is supplied to the CD-autochanger
by a feed from the radio cassette player.
Radio headphone amplifiers (high line system)
The rear mounted radio headphone amplifiers are located in the lower rear quarter trim casing and are held in position
by a clip on the side of the headphone amplifier. Mode and function buttons are located on a control panel, the mode
button allows each of the rear seat passengers to independently select from the radio, tape or CD-autochanger. The
driver and the rear seat passengers can each listen to any of the audio devices they select. However the radio
cassette setting has overall priority e.g:
lIf the radio cassette is using a radio wave band (AM or FM), the headphone user will be able to select the cassette
tracks or CD-autochanger. The user will be able to listen to same radio band that is selected on the radio
cassette, but will not be able to change the station selected.
lIf the radio cassette has CD-autochanger selected, the headphone amplifiers will allow listening to the compact
disk but will not allow track changes. The headphone user will be able to select on all of the radio bands or
cassette tracks.
lIf the radio cassette has tape selected, the headphone amplifiers will allow listening to the tape but will not allow
track changes. The headphone user will be able to select all radio bands or CD's on the CD-autochanger.
If one headphone amplifier unit has control of the tape player, CD or radio, the other headphone amplifier will be able
to listen and be able to change tape tracks or radio bands. Other buttons allow a search seek function of radio band
or compact disk track, reversal of the tape, radio station and volume adjustment depending on the current operating
mode. If one radio headphone amplifier has control of the radio, tape or CD autochanger the other radio headphone
amplifier is able to change the track or radio band selected. A headphone socket with a glow ring is located on the
control panel. When a headphone is turned on , a 'headphone-module active' signal is sent to the radio cassette
player. The design incorporates panel illumination and a glow-ring to locate the socket in low light conditions. To
control the audio output from the radio headphone amplifiers, signals are sent to and received from the radio cassette
player.