change time LAND ROVER DISCOVERY 2002 Owner's Manual

BODY CONTROL UNIT
86-3-26 DESCRIPTION AND OPERATION
If the ignition switch is in the off or crank position, the rear wipers are not active and the rear wiper enable output is
switched off.
In the event of a communications link failure occurring while the rear intermittent wipe programme is in operation, the
rear wiper enable output is switched off.
Reverse gear wipe
The BCU changes the operation of the rear wiper when the front wiper is active and reverse gear is selected. The rear
wiper operation rate used when the preconditions have been satisfied depend on the prevailing front wiper operating
mode and the position of the rear wiper switch. If the rear wiper is on or the front wiper is operating at an intermittent
rate when reverse gear is selected, the BCU will operate the rear wiper continuously for 4 seconds via the IDM. After
the initial period, the rear wiper will operate at the same rate as the front wiper.
The BCU checks for the following inputs to determine when to provide the rear wiper enable signal if the vehicle is in
reverse gear:
lIgnition state.
lRear wiper switch.
lFront intermittent wiper rate.
lReverse gear selected.
lFront intermittent wiper switch.
lFront wiper switch state.
lFront wash/ wipe in progress flag.
In the event of a communications link failure occurring while the reversing wipe is in operation, the rear wiper enable
output is switched off.
Headlamp wash
The headlamp wash will only operate when the headlamps are on, and then only every third time the front windscreen
wash button is pressed. When the BCU operates the headlamp washers, it activates the washer pump relay for a
period of 500 ms. The BCU supplies an earth path for the coil of the power wash relay located in the engine
compartment fuse box when the washer function is selected.
The BCU checks for the following inputs to determine when to provide power to the headlamp power wash relay:
lIgnition state.
lFront washer pump switch.
lDipped beam.
lMain beam state.
If the ignition switch is in the off position, the headlamp power wash relay is also held off. if the ignition state is crank,
the headlamp power wash relay is switched off and the headlamp power wash counter is reset to 0.
In the event of a communications link failure occurring while the headlamp power wash relay in on , the relay remains
on until the 500 ms timer has completed, then the relay is switched off.
Electric seats
The BCU can be programmed to operate the electric seats according to one of three options:
lOption 1 – no electric seats.
lOption 2 – normal.
lOption 3 – operates with ignition only.
To determine when to provide an output to the passenger and drivers seat enable relay, the BCU checks the condition
of the following inputs:
lIgnition state.
lTransit mode.
lDriver's door open.

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-29
Courtesy headlamps
This feature activates the headlamps for 30 seconds when the lock button on the remote transmitter is held down for
longer than 1 second. The headlamps will extinguish if the BCU receives either a lock or an unlock signal from the
remote transmitter.
The BCU checks the status of the following inputs to determine the correct qualifying conditions for requesting
courtesy headlamps:
lIgnition state.
lRemote locking request.
lRemote unlocking request.
lLazy locking request.
If the ignition is off and a lazy locking request is received, the courtesy headlamps are switched on and an internal
timer is turned on in the BCU which operates for 30 seconds. If the 30 second timer expires or a request for remote
locking or remote unlocking is received, the courtesy headlamps will be turned off.
When main beam is selected, the IDM also provides a signal to the instrument pack to switch on the main beam
warning lamp. An additional signal 'main beam indicator disable' is used to prevent the daylight running lamps
illuminating the main beam indicator when the main beam is in the daylight running lamp state and the main beam
indicator disable signal is on.
Lights on alarm
The lights on alarm in the instrument pack operates when the driver's door is open and the side lamps or headlamps
are on. The system uses inputs from the driver's door switch and the lighting switch to determine the logical conditions
that need to occur for switching on the alarm. The BCU carries out the logic operation and communicates with the
instrument pack using the serial data bus; the instrument pack will be requested to sound the alarm if the logic inputs
indicate that the driver's door is open with the lights still on.
Supply voltage is provided through the lighting switch to the IDM which acts as the signal line to indicate that the lights
are on for the logic circuits in the IDM and BCU. When the driver's door is opened, a second feed is supplied to the
BCU through the driver's door switch to indicate the condition. In this logic condition (lights on and driver's door open)
the BCU signals the instrument pack to operate the audible warning. If the lights are switched off or the driver's door
is closed the logic condition will be changed and the audible warning will be switched off.
Daylight running lamps
The BCU operates the daylight running lamps (where fitted) via the IDM. The daylight running lamps option can be
programmed in one of three states dependent on market/ customer requirements, these are:
lOption 1– no daylight running lamps.
lOption 2 – on with main beam off.
lOption 3 – on with main and dipped beam off and gearbox not in Park.
The BCU will ensure the logical conditions are satisfied for the lamps to operate under the set conditions. The BCU
checks the status of the following inputs to determine the logic action for providing an output to the daylight running
lamp relay:
lMain beam state.
lEngine running (link from instrument pack).
lDipped beam.
lGearbox state.
A voltage supply is fed to the coil of the daylight running lamp relay and the IDM. When the preconditions are satisfied
for daylight running lamp operation, the BCU sends a signal for the IDM to complete the circuit to earth to switch on
the daylight running lamps. The logical inputs are checked to ensure that the engine is running before switching the
relay to turn on the daylight running lamps. The engine running signal has to be present for at least 2 seconds before
the daylight running lamp relay can be switched on.

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-31
The BCU checks the status of the following inputs to determine the logic action for providing an output to the rear fog
lamp relay:
lIgnition state.
lMain beam state.
lDipped beam.
lFront fogs relay.
lRear fogs selected (press button, not latched).
If the ignition state is crank the state of the rear fog relay is memorised and the relay is switched off. Pressing the front
fog switch during cranking will not be recognised. When the ignition state returns to Ignition after cranking, the
memorised rear fog relay state is restored. If the ignition is turned off, the rear fog relay is turned off.
In the event of a communications link failure occurring while the rear fog relay is on, the rear fog relay will remain on
until the ignition is turned off or the dipped/ main beam is turned off.
Interior courtesy lamps
To determine when to provide an interior courtesy lamps enable output, the BCU checks the following input
conditions:
lIgnition state.
lTransit mode.
lDriver's door open.
lPassenger or rear door open.
The courtesy lamps operate at full brightness when they are first switched on. The BCU then gradually dims the lamps
(fade-out) before completely switching them off. Fade-out occurs over a period of two seconds following the logical
control signal to turn off the lights. When a door is opened, the BCU provides earth paths from the interior lamps, the
load space lamp and the ignition switch illumination. The following table lists the courtesy lamps operation and
duration for holding the lamps on that occurs after the BCU has detected a condition that signals the courtesy lamps
should be switched on:
Instrument pack
The BCU communicates with the instrument pack to provide a range of functions.
Control signal Additional conditions Duration
Door open - 10 minutes
Unlock signal from remote transmitter All doors closed and ignition switch not in
position III1 minute
Unlock signal from the driver's door lock All doors closed and ignition switch not in
position III1 minute
Ignition switch turned from position II or III
to position 0All doors closed 1 minute
Door changed from open to closed All other doors closed and ignition switch
not in position III15 seconds
Ignition switch in position III - Timer cancelled
BCU receives a lock command - Timer cancelled
Vehicle has transit mode enabled - 15 seconds on all occasions

ALARM SYSTEM AND HORN
86-4-10 DESCRIPTION AND OPERATION
Volumetric sensors
The BCU uses volumetric sensors to detect any change in air movement within the vehicle. There are two sensors
located in the headlining of the vehicle.
Input/Output
The sensors require a regulated power supply of 12 volts, via the BCU. When a change in air movement is detected
the sensors generate a 5 Hz pulse train to the BCU.
Each of the sensors have a dedicated signal input to the BCU. Power to the sensors is supplied by the BCU.
TestBook provides the ability to monitor the real time state of the sensors.

DRIVING AIDS
86-8-10 DESCRIPTION AND OPERATION
Operation
PDC System Operation
When the ignition switch is in position II and reverse gear is selected, the PDC sensors are automatically activated.
The PDC ECU only activates the system if reverse is selected for more than 1 second. This avoids nuisance audible
warnings when the gear selector lever is being moved between Drive and Park on vehicles with automatic
transmission.
When the system is activated, the PDC ECU illuminates the indicator LED in the PDC switch, switches on the
ultrasonic sensors and generates a single chime on the PDC sounder to indicate the system is active. If an object is
range of the sensors when the system is activated, a series of audible warnings are emitted by the PDC sounder
immediately.
If PDC operation is not required, it can be suspended temporarily by pressing the PDC switch. When reverse is
deselected and subsequently reselected, PDC will automatically become active again.
PDC can also be manually selected when not in reverse gear by pressing the PDC switch. A second press of the
switch is required to turn off the PDC or the PDC will be deactivated if reverse is selected and then deselected.
Sensor Operation
The PDC ECU processes the distance readings from the ultrasonic sensors to determine if there are any objects
within the detection areas. If there are no objects in the detection areas, there are no further audible warnings. If an
object is detected, repeated audible warnings are produced on the PDC sounder.
The maximum detection range is 1800 mm (70 in). When an object is detected, the time delay between the audible
warning tones decreases as the distance between the detected object and the vehicle decreases until, at
approximately 450 mm (17 in), the audible warning tone is continuous.
After the initial detection of an object, if there is no decrease in the distance between an object and the central sensors,
the time delay between the audible warnings remains constant. If an object is detected by one of the corner sensors
only, the audible warnings stop after about 5 seconds if there is no change in the distance between the object and the
corner sensor.

NAVIGATION SYSTEM
87-2 DESCRIPTION AND OPERATION
Description
General
The navigation system provides audio and visual route guidance to help the driver reach a selected destination. The
system is an optional fit consisting of a Traffic Pro navigation computer and antenna, manufactured by Harman/
Becker Automotive Systems, which are fitted in place of the In Car Entertainment (ICE) head unit and antenna.
Compact Disc (CD) and radio functions are incorporated into the navigation computer.
The navigation system allows the driver to choose between the shortest and fastest routes between the vehicle's
current position and a selected destination, and to select a stopover point in the journey and a route that avoids
motorways, ferries and toll roads. Directions to Points Of Interest (POI) e.g. airports, hospitals, petrol stations etc,
either local, national or in another country, can also be selected. A traffic jam function enables the driver to request
diversion instructions, around an obstructed part of the selected route, during the journey. A Traffic Management
Control (TMC) function, currently only available in some European countries, monitors traffic broadcasts and
automatically selects an alternative route during the journey if the original route is effected by a traffic jam, accident
or road works etc.
The position of the vehicle is determined by the navigation computer using a combination of vehicle sensor inputs and
radio signals from the 24 Global Positioning System (GPS) satellites orbiting the earth. The position of the vehicle is
then plotted on a digitised map, loaded into the navigation computer from a CD-ROM, to determine the journey route
and provide the route guidance.
The GPS satellite signals are used for initial determination of the vehicle's position and periodic position updates. The
vehicle sensor inputs are used to monitor the vehicle's direction of travel and distance travelled between position
updates from the GPS satellite signals. The vehicle sensor inputs consist of:
lA vehicle speed signal from the ABS ECU, to monitor the distance travelled and for automatic volume control.
lA reverse gear signal from the selector and inhibitor switch of the automatic gearbox, or reverse gear switch of
the manual gearbox, to enable the navigation computer to differentiate between forward and rearward movement
of the vehicle.
lA gyro in the navigation computer, to monitor changes of direction, i.e. steering inputs.
The signal from each GPS satellite contains information about satellite position, almanac data and time (almanac data
is the current status of the satellite). Signals from between five and 11 of the GPS satellites can be received at a given
point on the earth's surface at any one time. The number and quality of separate GPS satellite signals received also
varies with vehicle location. In hilly or tree lined areas, built up areas with tall buildings, multi-storey car parks,
garages, tunnels, bridges and during heavy rain/thunderstorms, signal reception of some or all of the GPS satellites
will be poor or non existent.
A minimum of three separate GPS satellite signals are required for the navigation computer to calculate a three
dimensional (3D) positional fix. When only two signals are being received, the navigation computer will calculate a
less accurate two dimensional (2D) positional fix. The more widely dispersed that the GPS satellites are, the more
accurate the positional fix. The navigation computer can store information from a maximum of 12 GPS satellites at
any one time. When more than three signals are stored, the navigation computer selects the three most widely
dispersed signals for the position calculation.
GPS Antenna and diplexer unit
The GPS antenna is installed at the rear of the roof on the centreline. A diplexer unit on the underside of the GPS
antenna amplifies the radio signals received from the GPS satellites and transmits them through separate dedicated
co-axial cable to the navigation computer for processing.

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.

NAVIGATION SYSTEM
DESCRIPTION AND OPERATION 87-5
System Settings Menu
The system settings menu provides access to features that can be changed to suit market and personal preferences
and to navigation system operating features. On European systems, the system settings menu also includes
computer games and a currency converter. While the navigation computer is in the navigation mode, the system
settings menu can be accessed by pressing the Nav button. Using the RH rotary control, the following features can
be selected and adjusted:
lTIME – Allows the navigation system clock to be set to local time as opposed to the Greenwich Mean Time (GMT)
transmitted from the GPS satellites. The local time setting is necessary for correct navigation on routes with time
restrictions and for Estimated Time of Arrival (ETA) calculations. The time can only be adjusted in 30 minute
steps.
lSAVE POSITION– Allows the current vehicle position to be saved and allocated a name in the navigation
destination memory.
lGAMES – Provides access to a selection of computer games.
lLANGUAGE– Allows the navigation system language and voice (where applicable) to be changed.
lANIMATIONS– Allows the LCD animations to be switched on and off.
lMEASURING UNIT – Allows the route guidance distances displayed on the LCD to be switched between metric
and Imperial units.
lANNOUNCEMENT ETA – Allows the route guidance ETA announcement to be switched on and off.
lCALCULATE EURO – Provides access to a currency converter.
User Menu
The user menu provides access to further features that can be changed to suit personal preferences. While the
navigation computer is in navigation, radio or CD modes, the user menu can be accessed by pressing and holding
the tone button for more than 2 seconds. The user menu is displayed over two screens, which can be toggled between
using the

multifunction button. Using the appropriate multifunction button or the RH rotary control, the following
settings can be selected and adjusted:
Screen 1
lGal – Automatic volume control setting (see above).
lTel – If a handsfree telephone system is connected to the navigation computer, allows either mute (telephone
mute mode) or audio signal (telephone conversation via the ICE speakers) to be selected.
lLcd – The LCD can be set to appear negative, positiveor automatic. In automatic, the display will be positive or
negative, depending on the setting of the exterior lamps.
lLed – A Light Emitting Diode (LED) in the display can be set to off or blinking. When set to blinking, the LED
flashes when the navigation computer is switched off.
lM/S – Radio reception can be set to Stereo, Mono or Auto, to suppress interference and reflections and so
optimise reception. Stereo is for exceptionally good reception conditions. Mono is for poor reception conditions.
In auto, the normal setting, the navigation computer automatically switches between stereo and mono depending
on reception conditions.
Screen 2
lNav – Sets how audio navigation instructions are delivered. In onl, other audio sources are suppressed and only
the navigation instruction is output to the speakers. In mixed, the volume of any other audio source is reduced
and the volume of the navigation announcement is the same as the original audio source +/– 6 dB (adjustable).
In independ, the audio source and navigation announcement can be set to independent volume levels.
lAux – Used to switch auxiliary CD AF connections between Aux mode on and Aux mode off. If no CD
autochanger is installed, an external cassette or CD player can be connected to the navigation computer and
powered by switching on the auxiliary CD AF connections.
lCmp – Allows a compass to be shown on the LCD when route guidance is not active.
lBeV – Used to adjust the signal tone volume. Signal tones sound to confirm storage confirmation etc. and can
be set between 0 (quiet) and +5 (loud).

NAVIGATION SYSTEM
87-6 DESCRIPTION AND OPERATION
Service Menu
The service menu provides access to details of the navigation computer hardware and software, and can be accessed
when the navigation computer is in radio mode, by simultaneously pressing the NAV button and the 10 multifunction
buttons. The following items can then be scrolled through by pressing the Nxt (next) and Prv (previous) multifunction
buttons, or turning the RH rotary control:
lModel No.
lSerial No.
lChanger Reset
lGAL
lRadio Software
lRadio Bolo
lNavi Rom
lNavi Flash
lRTC Value
When Changer Reset is displayed, the CD autochanger (where fitted) can be reset by pressing the appropriate
multifunction button.
When the End multifunction button is pressed, the navigation computer quits the service menu and returns to radio
mode.
Garage Menu
Garage menu enables the navigation system to be tested and calibrated, and also contains a route navigation
demonstration. The garage menu is entered from the main navigation menu, as follows:
1Press the Nav button to access the system settings.
2Press and hold multifunction button 3, then press multifunction button 5 to display the garage menu.
The garage menu contains the following, which can be accessed using the RH rotary control:
lCALIBRATION RIDE – Used to calibrate the navigation computer, to enable route navigation.
lGPS INFO– Provides functional test of antenna by checking GPS reception. If functioning correctly, displays the
number of satellites being received, the date, time (Greenwich Mean Time) and the type of positional fix currently
possible.
lCALIBRATION– Allows vehicle specific calibration data to be entered, e.g. tyre size. Also allows current
calibration to be deleted prior to re-calibrating.
NOTE: Only known calibration data should be entered. The navigation computer cannot make route
calculations if incorrect data is entered.
lSENSORS– Allows wheel speed, reverse gear and gyro sensor inputs to be checked.
lVERSION– Displays navigation computer hardware and software details.
lSPEECH TEST– Performs a test of the navigation computer audio output.
lMODULE TEST– Performs a test routine on the internal components of the navigation computer.
lDEMO – Allows a route navigation demonstration to be run.
To quit the garage menu, press the Nav button.
Calibration
Calibration is required after initial installation or replacement of the navigation computer. It may also be necessary
after repairs to system wiring and if route navigation becomes inaccurate or fails to operate. If the navigation computer
contains an existing calibration, this must be deleted, using the garage menu, prior to running the new calibration
routine. The sensor inputs should also be checked before running the calibration routine.

NAVIGATION SYSTEM
87-8 DESCRIPTION AND OPERATION
17After calibration is achieved, return to the dealership, park the vehicle and stop the engine.
18Turn the ignition switch to position I.
19Use the system settings menu to set the navigation computer to local time and the required units of measure:
aPress the Nav button.
bTurn the RH rotary control to scroll through the displayed menu, highlight TIME and press the RH rotary
control to select. Press the + or – multifunction button to adjust the time in 30 minute steps. Select the 24
hour clock and confirm by pressing the OK multifunction button.
cIf metric units of measure are required, go to step e) (the navigation computer defaults to metric units of
measure).
dIf Imperial units of measure are required, turn the RH rotary control to scroll through the displayed menu,
highlight MEASURING UNIT and press the RH rotary control to select. Turn the RH rotary control to
highlight IMPERIAL and press the RH rotary control to select.
ePress the Nav button to return to the destination menu.
20Calibration is complete. The navigation system is ready for use.
NOTE: The accuracy of the system will automatically be fine tuned when a further journey is made, but this is not
required as part of the calibration procedure.
NOTE: In European countries, the territory will have to be set the first time the navigation system is used, and the
first time a destination in another country is selected. The first time the navigation system is used or a destination
in another country is selected, a map is displayed with the default/current territory highlighted. To change the
territory: Press the RH rotary control to display the territory list; turn the RH rotary control to scroll through the
list and highlight the required territory; press the RH rotary control to confirm the selection.
A = Distance, miles (km); B = Start/Finish point
Reset
If the navigation system malfunctions, a system reset can be triggered by simultaneously pressing the TP button and
multifunction button 1 or 3. The navigation CD will need to be installed after the system reset.