2002 LAND ROVER DISCOVERY display

AIR CONDITIONING
DESCRIPTION AND OPERATION 82-17
RH temperature. Illuminates to show the RH temperature selection, external air temperature or diagnostic fault code.
Blower speed. Illuminates when the blower speed is manually selected. Also illuminates in the automatic modes when
one of the temperatures is set to LO or HI.
External air temperature. EXT illuminates to show that external air temperature is selected on.
All temperature indications on the display are in either
°C or °F. For 1 second after the system is first switched on, the
display shows only
°C or °F, in the LH temperature window, to indicate which temperature scale is in use. After 1
second, the
°C or °F indication goes off and the display shows all relevant outputs.
Temperature conversion: While the system is on, the temperature indications on the display can be switched between
the two scales by pressing and holding the fresh/recirculated air switch, then pressing and holding the A/C on/off
switch until the audible warning sounds (approximately 3 seconds).
Dual pressure switch
The dual pressure switch protects the refrigerant system from extremes of pressure. The normally closed switch is
installed in the top of the receiver drier. If minimum or maximum pressure limits are exceeded the switch contacts
open, causing the compressor clutch to be disengaged. The minimum pressure limit protects the compressor, by
preventing operation of the system unless there is a minimum refrigerant pressure (and thus refrigerant and
lubricating oil) in the system. The maximum pressure limit keeps the refrigerant system within a safe operating
pressure.
Dual pressure switch nominal operating pressures
Evaporator temperature sensor
The evaporator temperature sensor is an encapsulated thermistor that provides the ATC ECU with an input of the
evaporator air outlet temperature. The evaporator temperature sensor is installed in a clip which locates in the
evaporator matrix in the heater assembly. The ATC ECU uses the input to prevent the formation of ice on the
evaporator.
In-car temperature sensor
The in-car temperature sensor is an encapsulated thermistor that provides the ATC ECU with an input of cabin air
temperature. The sensor is integrated into the inlet of an electric fan, which is installed behind a grille in the fascia
outboard of the steering column. The fan runs continuously, while the ignition is on, to draw air through the grille and
across the sensor.
Sunlight sensor
The sunlight sensor consists of two diodes that provide the ATC ECU with inputs of light intensity, one as sensed
coming from the left of the vehicle and one as sensed coming from the right. The inputs are used as a measure of the
solar heating effect on vehicle occupants. The sensor is installed in the centre of the fascia upper surface.
Heater coolant temperature sensor
The heater coolant temperature sensor is an encapsulated thermistor that provides the ATC ECU with an input related
to heater matrix coolant temperature. The sensor is installed in the casing of the heater assembly and presses against
the end tank of the heater matrix.
Ambient temperature sensor
The ambient temperature sensor is an encapsulated thermistor that provides the ATC ECU with an input of external
air temperature. The sensor is attached to the cooling fan mounting bracket in front of the condenser.
Limit Opening pressure, bar (lbf.in2) Closing pressure, bar (lbf.in2)
Minimum 2.0 (29.0), pressure decreasing 2.3 (33.4), pressure increasing
Maximum 32 (464), pressure increasing 26 (377), pressure decreasing

AIR CONDITIONING
DESCRIPTION AND OPERATION 82-21
Diagnostics
The ATC ECU performs a diagnostic check each time the ignition is switched on. To avoid nuisance fault indications
at low light levels, the sunlight sensor is omitted from the diagnostic check. If a fault is detected, the audible warning
sounds three times and the AUTO window on the control panel display flashes for 20 seconds. The ATC ECU then
reverts to normal control but uses a default value or strategy for the detected fault. Faults are identified by performing
a manual diagnostic check of the system.
A manual diagnostic check includes a check of the sunlight sensor, and is initiated by pressing and holding the AUTO
switch and the air distribution switch, then turning the ignition switch from off to on. The audible warning sounds once
and the indications on the control panel display illuminate. FC is shown in the LH temperature window and the results
of the check are shown as a two digit fault code in the RH temperature window. If a fault is detected, the audible
warning sounds three times and the AUTO window on the display flashes on and off for 20 seconds. If more than one
fault is detected, the fault codes cycle in numerical order, at 1 Hz. The audible warning sounds as each fault code is
shown. In low light conditions, to avoid false sunlight sensor fault indications, the sunlight sensor should be illuminated
with a strong light source.
Diagnostic fault codes and fault descriptions
Code Component Fault Default value/strategy
00 - No fault found -
11 In-car temperature sensor Open or short circuit 25°C (77°F)
12 Ambient temperature sensor Open or short circuit 10°C (50°F)
Cooling fan permanently on
Display shows "- -" if external
air temperature selected
13 Thermistor Open or short circuit 0°C (32°F)
14 Heater coolant temperature sensor Open or short circuit 70°C (158°F)
21 Sunlight sensor, left output Open or short circuit No solar heating correction
22 Sunlight sensor, right output Open or short circuit No solar heating correction
31 LH temperature servo motor Open or short circuit
Motor or flap mechanism seizedServo motor locked in position
32 RH temperature servo motor Open or short circuit
Motor or flap mechanism seizedServo motor locked in position
33 Distribution servo motor Open or short circuit
Motor or flap mechanism seizedServo motor locked in position

BODY CONTROL UNIT
86-3-16 DESCRIPTION AND OPERATION
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.
Cruise control
The BCU processes several signals used for cruise control:
lWhen the brake pedal is pressed, a low voltage brake lamp signal is sent via the BCU to the cruise control ECU.
lThe gear position switch sends an input via the BCU to the cruise control ECU if the selector lever is in Park,
Neutral or Reverse.
lA voltage supply is fed from the BCU to the cruise control SET+ switch.
lA voltage supply is fed from the BCU to the cruise control RES switch.
On vehicles with automatic transmission, if the BCU receives an input from the gear position switch or the brake pedal
switch, the BCU sends a signal to the cruise control ECU to cancel or inhibit cruise control operation.

+ ENGINE MANAGEMENT SYSTEM - Td5, DESCRIPTION AND OPERATION, Description.

+ ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - cruise control.
Shift interlock (where fitted)
On automatic gearbox models, the BCU and IDM combine with an interlock relay located in the passenger
compartment fuse box to operate a shift interlock solenoid, so that the gear selector lever cannot be moved out of
Park until certain logical conditions have been satisfied. Operation of the interlock may be affected, if the battery
becomes discharged.

+ AUTOMATIC GEARBOX - ZF4HP22 - 24, DESCRIPTION AND OPERATION, Description.

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
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.
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.

NAVIGATION SYSTEM
DESCRIPTION AND OPERATION 87-3
Navigation Computer
The navigation computer is installed in the DIN radio slot in the fascia. A spring loaded catch on each side of the
navigation computer secures it in position. Slide tools, installed in slots at the bottom front corners of the navigation
computer, are required to unlock the catches during removal.
The navigation computer contains all the hardware and software required for control of the navigation, radio and CD
systems, including the GPS receiver and a solid state piezo gyro for the navigation system. The piezo gyro measures
the motion of the vehicle around its vertical axis.
The controls for the navigation computer are all located on the front panel of the unit. The centre section of the front
panel hinges to allow access to the CD player and, for security purposes, can be removed from the unit. The controls
perform the following functions:
lOn/Off (ON) button, for switching the unit on and off.
lTone button, for activating the tone menu to adjust bass, treble, balance, fade and loudness functions.
lTraffic Programme (TP) button, for activating the traffic information programme menu (Europe only).
lCompact Disc (CD) mode button, for selecting CD operation.
lRadio (Rad) mode button, for selecting radio operation and tuning menus.
lNavigation (Nav) mode button, for entry and exit of the navigation menu and service mode.
lCD eject button, opens the removable panel and ejects the CD.
lRH rotary control, scrolls through menus when turned and enters a selection when pressed. Also mutes audio
navigation instructions when pressed in navigation mode.
lMultifunction buttons, for entering the security code and menu selections.
lLiquid Crystal Display (LCD), green screen that displays navigation, radio and CD information.
lLH rotary control, adjusts volume when turned. When pressed, restores, repeats or interrupts audio navigation
instructions or provides destination details.
1On/Off button
2Tone button
3Traffic programme button (Europe only)
4CD mode button
5Radio mode button
6Navigation mode button7CD eject button
8RH rotary control
9Release tool slot
10Multifunction buttons
11LCD
12LH rotary control

NAVIGATION SYSTEM
87-4 DESCRIPTION AND OPERATION

Inputs and Outputs
In addition to the vehicle sensor and the antenna inputs, the navigation computer also receives the following:
lA permanent battery feed from the passenger compartment fusebox, to power the navigation function.
lAn ignition switched battery feed from the passenger compartment fusebox, to power the navigation, radio and
CD functions when the ignition switch is in positions I and II.
lAn illumination power feed for switch illumination and LCD backlighting when the exterior lights are on.
Navigation computer outputs consist of those for the ICE system speakers and to the auxiliary CD autochanger, where
fitted.
Security Code
The navigation computer is programmed with a five digit security code selected from numbers 1 to 7. If the battery or
the navigation computer are disconnected, the code is requested on the LCD the first time the navigation computer
is switched on after reconnection; this also occurs if a different removable panel is fitted.
The code is entered using the appropriate multifunction buttons. The navigation computer automatically starts to
operate when the fifth digit of the correct code is entered. If an incorrect code is entered, CODE is displayed on the
LCD to prompt another entry attempt. If an incorrect code is entered three times in succession, WAIT is displayed on
the LCD and the unit is disabled for approximately 60 minutes. If the navigation computer is switched off, the
remaining disabled time will resume when the power is restored.
Automatic Volume Control (AVC)
The AVC feature automatically increases and decreases the audio volume with increases and decreases of vehicle
road speed. The AVC feature, also known as the GAL setting, uses the vehicle speed signal from the ABS ECU and
can be turned off or adjusted to start at a different vehicle speed. The GAL setting is accessed through the User Menu
and can be set to between 0 and +15, where 0 is off and +1 to +15 progressively increase the vehicle speed at which
AVC starts to operate.