gearbox LAND ROVER DISCOVERY 2002 Workshop Manual
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 2002, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 2002Pages: 1672, PDF Size: 46.1 MB
Page 1273 of 1672

PANEL REPAIRS
77-2-24 REPAIRS
Refit
1.Fit centre braces.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit crush cans.
4. Models with A/C: Fit A/C pipes.
5.Fit RH horn.
+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
6.Fit headlamp wiring and headlamp levelling
motors.
7.Fit RH and LH headlamps.
+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
8. Diesel models: Fit gearbox fluid cooler.
9. Models with A/C: Fit condensor.
+ AIR CONDITIONING, REPAIRS,
Condenser.
10.Fit washer reservoir.
+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
11.Connect leads/multiplug to alternator.
12.Connect battery leads, negative lead last.
Headlamp mounting panel - RH
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove front bumper assembly.
+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
4. Models with A/C: Remove condensor.
+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove RH headlamp.
+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Remove RH repeater lamp.
+ LIGHTING, REPAIRS, Lamp - front
repeater.
8.Release headlamp levelling motor and position
aside.
9.Release headlamp wiring and position aside.
10.Remove battery and battery tray.
+ CHARGING AND STARTING,
REPAIRS, Battery.
11.Remove horn.
+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
12.Remove RH crush can.
13.Remove 2 bolts securing front bulkhead
assembly to chassis.
14.Remove RH centre brace.
Page 1274 of 1672

PANEL REPAIRS
REPAIRS 77-2-25
Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit centre brace.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit crush can.
4. Models with A/C: Fit A/C pipes.
5.Fit horn.
+ ALARM SYSTEM AND HORN,
REPAIR, Vehicle horn.
6.Fit battery and battery tray. Do not connect
leads.
+ CHARGING AND STARTING,
REPAIRS, Battery.
7.Fit headlamp wiring and headlamp levelling
motors.
8.Fit repeater lamp.
+ LIGHTING, REPAIRS, Lamp - front
repeater.9.Fit headlamp.
+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
10. Diesel models: Fit gearbox fluid cooler.
11. Models with A/C: Fit condensor.
+ AIR CONDITIONING, REPAIRS,
Condenser.
12.Fit bumper assembly.
+ EXTERIOR FITTINGS, REPAIRS,
Bumper assembly - front.
13.Connect leads/multiplug to alternator.
14.Connect battery leads, negative lead last.
M77 1741A
Page 1275 of 1672

PANEL REPAIRS
77-2-26 REPAIRS
Headlamp mounting panel - LH
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove washer reservoir.
+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
4. Models with A/C: Remove condensor.
+ AIR CONDITIONING, REPAIRS,
Condenser.
5. Diesel models: Remove gearbox fluid cooler.
6.Remove headlamp.
+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
7.Remove repeater lamp.
+ LIGHTING, REPAIRS, Lamp - front
repeater.
8.Release headlamp levelling motor and position
aside.
9.Release headlamp wiring and position aside.
10.Remove air filter assembly.
+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.
+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
11.Remove 2 earth leads from LH of front
bulkhead.
12.Release and remove A/C pipes.
13.Remove crush can.
14.Remove bonnet release cable.
15.Remove 2 bolts securing front bulkhead
assembly to chassis.
16.Remove centre brace.Repair
1.Remove existing panel(s), prepare panel joint
faces and install new panel(s) in accordance
with Panel Replacement Procedure. Punch or
drill holes in new panel for plug welding as
shown.
Refit
1.Fit centre brace.
2.Fit 2 bolts securing bulkhead to chassis and
tighten bolts to 45 Nm (33 lbf.ft).
3.Fit bonnet release cable.
4.Fit crush can.
5. Models with A/C: Fit A/C pipes.
6.Fit 2 earth leads to LH of front bulkhead.
7.Fit air filter assembly.
+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.
+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
8.Fit battery tray.
9.Fit headlamp wiring and headlamp levelling
motors.
10.Fit repeater lamp.
+ LIGHTING, REPAIRS, Lamp - front
repeater.
Page 1276 of 1672

PANEL REPAIRS
REPAIRS 77-2-27
11.Fit headlamp.
+ LIGHTING, REPAIRS, Headlamp - up
to 03MY.
12. Diesel models: Fit gearbox fluid cooler.
13. Models with A/C: Fit condensor.
+ AIR CONDITIONING, REPAIRS,
Condenser.
14.Fit washer reservoir.
+ WIPERS AND WASHERS, REPAIRS,
Reservoir - washer - up to 03MY.
15.Connect leads/multiplug to alternator.
16.Connect battery leads, negative lead last.
Valance upper assembly - LH
In this procedure, the front wing, the valance outer
reinforcement and the bonnet alarm switch mounting
bracket are replaced in conjunction with the LH
valance upper assembly.
Remove
1.Disconnect both battery leads, negative lead
first.
2.Disconnect leads/multiplug from alternator.
3.Remove front wing.
+ EXTERIOR FITTINGS, REPAIRS,
Wing - front - up to 03MY.
4.Remove air filter assembly.
+ ENGINE MANAGEMENT SYSTEM -
V8, REPAIRS, Air cleaner assembly.
+ ENGINE MANAGEMENT SYSTEM -
Td5, REPAIRS, Air filter assembly.
5.Remove PAS/ACE reservoir.
6.Remove ABS modulator.
+ BRAKES, REPAIRS, Modulator unit
- ABS.
7.Remove brake pipes from valance.
8.Release harness from valance and position
aside.
9. Models with A/C: Depressurise A/C system
and remove pipes from valance.
+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
Page 1478 of 1672

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-9
IDM outputs
The IDM receives the following signals from the BCU using the serial datalink to provide power outputs:
Description Signal type System
Unlock all doors enable Digital Locking/ Unlocking/ Alarm
Lock passenger and rear doors enable Digital Locking/ Unlocking/ Alarm
Superlock all doors enable Digital Locking/ Unlocking/ Alarm
Lock driver's door Digital Locking/ Unlocking/ Alarm
Rear fog lamps enable Digital Exterior lighting
Daylight running lamps enable Digital Exterior lighting
LH direction indicators enable Digital Direction indicators/ Hazard warning/ Alarm
RH direction indicators enable Digital Direction indicators/ Hazard warning/ Alarm
Gear position indicator illumination Digital Illumination
Headlamp main beam indicator disable Digital Illumination
Front wiper enable Digital Wipers and washers
Rear wiper enable Digital Wipers and washers
Rear window enable Digital Power windows
Shift lever solenoid enable Digital Automatic gearbox
Transfer box solenoid enable/ Alarm sounder
relayDigital Gearbox
Heated rear window enable Digital Heated screens
Page 1480 of 1672

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-11
Programmable options
The BCU can be programmed with a number of options to satisfy specific market requirements and customer
preferences. The options can be set using TestBook.
Function Option Details
Transmission Manual The vehicle is fitted with manual transmission.
Automatic The vehicle is fitted with automatic transmission.
Front fog lamps None The vehicle is not fitted with front fog lamps.
Main The front fog lamps will operate if the headlamps are on main
beam.
No main The front fog lamps will not operate if the headlamps are on main
beam.
Interlocks None The vehicle is not fitted with key, shift or transfer box interlocks.
Shift The vehicle is fitted with key, shift and transfer box interlocks.
No transfer The vehicle is fitted with key and shift interlocks, but not a transfer
box interlock.
Daylight running lamps None The vehicle is not fitted with daylight running lamps.
No main The daylight running lamps are on if the headlamp main beams
are off.
No heads The daylight running lights are on with headlamp main and dipped
beams off and the gearbox not in Park.
Programmed wash/ wipe Normal The front wipers operate if the front wash is operated.
No wipe The front wipers do not operate if the front wash is operated.
Key-in warning Disabled The ignition key in audible warning is disabled.
Enabled The ignition key in audible warning is generated if the ignition key
is in and the driver's door is open.
Electric front seats None The vehicle is not fitted with electric front seats.
Normal Electric seat adjustment is available for 45 seconds after the
driver's door opens or if the ignition is on.
Ignition II Electric seat adjustment is available if the ignition is on.
Electric front windows Driver cancel The front windows will be disabled 44 seconds after the driver's
door is opened.
All cancel The front windows will be disabled 44 seconds after any door is
opened.
No cancel The front windows will be disabled when the ignition is turned off.
Heated front screen Fitted The vehicle is fitted with heated front screens.
None The vehicle is not fitted with heated front screens.
Rear windows and
sunroofDriver cancel The rear windows and sunroof will be disabled 44 seconds after
the driver's door is opened.
All cancel The rear windows and sunroof will be disabled 44 seconds after
any door is opened.
No cancel The rear windows and sunroof will be disabled when the ignition
switch is turned off.
Gear position indicator
illuminationAlways The automatic gearbox selector illumination is on when the
ignition is on.
Sidelights The automatic gearbox selector illumination is on when the
ignition is on and the sidelights are off.
Hill descent control None The vehicle is not fitted with hill descent control.
Fitted The vehicle is fitted with hill descent control.
Courtesy headlamps Disabled The vehicle is not fitted with courtesy headlamps.
Enabled The vehicle is fitted with courtesy headlamps.
Odometer error warning Disabled The odometer will not flash if there is an odometer error.
Enabled The odometer will flash if there is an odometer error.
Page 1484 of 1672

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-15
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.
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.
Page 1485 of 1672

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.
Page 1486 of 1672

BODY CONTROL UNIT
DESCRIPTION AND OPERATION 86-3-17
Ignition key interlock (where fitted)
On automatic gearbox models, the ignition key interlock solenoid prevents removal of the ignition key from the ignition
switch when the transmission gear selector is not in the Park position. The logic control operation for this is performed
by the BCU.
Transfer box interlock (where fitted)
On automatic gearbox models, a transfer box interlock solenoid is controlled by the IDM to prevent transfer box shift
lever being moved out of high or low range unless certain conditions have been satisfied. The IDM controls the
operation of the transfer box relay which is located in the passenger compartment fuse box.
+ TRANSFER BOX - LT230SE, DESCRIPTION AND OPERATION, Description.
Gear position switch
A gear position switch is located on the automatic gearbox and is used to inform the BCU of the gear selector lever
position. The BCU has four sensing inputs from the gear position switch contacts W, X, Y, Z, which are used to
determine the gearbox drive status at any particular instance. The BCU gives an output corresponding to the gearbox
status derived from the gear position switch inputs. The logic states defining the gear selector positions are listed in
the table below, where Z1, Z2, Z3 and Z4 represent intermediate states which exist as the selector lever position is
changed:
The existence of an intermediate state causes a fault code to be detected by the BCU. To reduce the chances of the
fault condition occurring while changing selector lever position, the inputs are debounced and only considered valid
when they have existed for at least 33 ms.
Transmission neutral selector
The transmission neutral sensor provides an earth signal to the BCU when the transfer box is in neutral. The earth
signal causes the BCU to operate an audible warning when the transfer box is in neutral with the ignition switched on.
+ TRANSFER BOX - LT230SE, DESCRIPTION AND OPERATION, Description.
Gear position Switch contacts
WX Y Z
P (Park) 1 0 0 0
Z11100
R (Reverse) 0 1 0 0
Z11100
N (Neutral) 1 1 1 0
Z21010
D (Drive) 1 0 1 1
Z31111
30111
Z40011
20001
Z40011
10010
Page 1487 of 1672

BODY CONTROL UNIT
86-3-18 DESCRIPTION AND OPERATION
Self levelling suspension and ABS
The BCU communicates with the SLABS ECU for several functions:
lAn output is provided from the SLABS ECU to the BCU to provide the logic conditions for issuing the SLS audible
warning.
lThe BCU receives an input from the SLABS ECU relating to the raise/ lower command from the remote handset.
+ REAR SUSPENSION, DESCRIPTION AND OPERATION, Description - SLS.
Hill descent control
The BCU provides an output signal to the SLABS ECU for automatic transmission in neutral for HDC control. The
BCU checks the status of the ignition and 'gearbox state' inputs and provides a 'Neutral selected' output. If the ignition
is on and 'gearbox state' is Neutral, the 'Neutral selected' output is on, otherwise 'Neutral selected' is off.
+ BRAKES, DESCRIPTION AND OPERATION, Description.
Heated screens
The Heated Front Screen (HFS) is fitted for some market destinations and is operated from a non-latching switch
located on the instrument pack cowl. The BCU will only allow the heated front screen to operate when the engine is
running and controls the time-out period for switching the circuit off.
The heated front screen operation can also be controlled from the Automatic Temperature Control (ATC) ECU on
vehicles fitted with air conditioning.
The heated rear window will only function when the engine is running, and is operated by a non-latching switch on the
instrument pack cowl. The heated rear window can also be operated by the ATC ECU on vehicles fitted with air
conditioning.
Interior courtesy lamps
The BCU controls the operation of the interior courtesy lamps. The courtesy lamps are situated in the front, mid and
rear areas of the headlining.
Fuel flap actuator
The BCU provides an earth path to the fuel flap release solenoid to allow the fuel filler flap to be opened. This is only
allowed if the alarm system is not set and all other conditions have been satisfied. The fuel flap release switch is
located in the fascia switch pack and it receives a voltage supply from the passenger compartment fuse box.
Audible warnings
The BCU can request the instrument pack to generate an audible warning in response to conditions it has detected
and which need to be drawn to the driver's attention. One of six different audible warnings can be requested by the
BCU.
Sound request number Sound functions Priority (1 = lowest, 6 = highest)
0Off 1
1 Seat belt warning 6
2 Key-in warning 3
3 SLABS/ HDC warning 4
4 Transfer box in neutral warning 5
5 Lights on warning 2