lock LAND ROVER DISCOVERY 2002 Workshop Manual

AIR CONDITIONING
82-10DESCRIPTION AND OPERATION
Heater assembly
1Distribution servo motor
2Refrigerant inlet and outlet connector block
3RH blend flap servo motor
4Thermostatic expansion valve
5LH blend flap servo motor
The heater assembly controls the temperature and distribution of air supplied to the distribution ducts, and is similar
to the heater assembly installed in non A/C vehicles.

+ HEATING AND VENTILATION, DESCRIPTION AND OPERATION, Description. The only differences from
the heater assembly in non A/C vehicles are as follows:
lThe thermostatic expansion valve, evaporator and evaporator temperature sensor are installed at the air inlet
side of the casing.
lThree servo motors operate the control flaps instead of control cables.
lA coolant temperature sensor is installed against the heater matrix.
The servo motors are controlled by the ATC ECU. Feedback potentiometers in the servo motors provide the ATC ECU
with flap position signals.

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

AIR CONDITIONING
DESCRIPTION AND OPERATION 82-25
Description
The rear air conditioning system cools and recirculates air at the rear of the cabin. The system consists of refrigerant
lines, a rear evaporator/blower assembly, a distribution system and a control panel.
Cooled air from the rear evaporator/blower assembly is supplied by the distribution system to vent outlets above each
second and third row seat. The system is controlled by two switches on the control panel.
Refrigerant lines
Two refrigerant lines connect the rear evaporator/blower assembly to the front A/C refrigerant system. The lines are
routed along the LH underside of the vehicle and secured to a connector block in the floor. A heat shield protects the
lines where they pass above the rear silencer.
Rear evaporator/blower assembly
1Resistor pack
2Thermostatic expansion valve
3Rear blower relay
4Air outlet
5Evaporator6Capillary tube
7Housing
8Condensate drain outlet
9Refrigerant lines
10Blower

AIR CONDITIONING
82-34REPAIRS
8.Remove 3 remaining bolts securing cooling fan
support rails to condenser.
9.Remove condenser.
10.Remove bolt securing adaptor block to receiver
drier.
11.Remove adaptor block from receiver drier and
discard 'O' ring.
CAUTION: Always fit plugs to open
connections to prevent contamination.12.Remove bolt securing condenser pipe to
receiver drier.
13.Remove clamp bolt receiver drier to bracket
and remove drier from bracket.
14.Remove and discard 'O' ring from condenser
pipe.
CAUTION: Always fit plugs to open
connections to prevent contamination.
15.Remove 2 remaining bolts securing receiver
drier brackets and condenser LH mounting
bracket to condenser.
16.Remove mounting bracket assembly.
17.Remove remaining bolt securing condenser RH
mounting and remove mounting.

AIR CONDITIONING
REPAIRS 82-35
18.Remove sealing strip from outer upper seam of
condenser.
19.Remove captive nut plates from condenser.
Refit
1.Fit captive nut plates to new condenser.
2.Fit seal to condenser.
3.Fit RH mounting bracket to condenser and
secure with bolt.
4.Fit receiver drier bracket assembly and secure
with bolts.
5.Ensure condenser pipe and new receiver drier
connections are clean.
6.Lubricate new 'O' ring with refrigerant oil and fit
to condenser pipe.
7.Fit receiver drier to bracket and condenser
pipe. Tighten bolt securing condenser pipe to 5
Nm (3.7 lbf.ft). Fit clamping bolt securing
receiver drier to bracket and tighten to 5 Nm
(3.7 lbf.ft).
8.Ensure adaptor block and receiver drier
connections are clean.
9.Lubricate new 'O' ring with refrigerant oil and fit
to adaptor block.
10.Fit adaptor block to receiver drier and tighten
bolt to 5 Nm. (3.7 lbf.ft).
11.Fit condenser assembly. 12.Fit cooling fan to condenser and fit bolts to
secure support rails to condenser brackets.
13.Ensure connections of condenser, receiver
drier and evaporator pipes are clean.
14.Lubricate new 'O' ring seals with refrigerant oil
and fit one seal to each evaporator pipe.
15.Connect evaporator pipes and tighten bolts to 5
Nm (3.7 lbf.ft).
16.Connect multiplug to dual pressure switch.
17.Fit radiator.
l

+ COOLING SYSTEM - Td5,
REPAIRS, Radiator.
l

+ COOLING SYSTEM - V8,
REPAIRS, Radiator.
18.Recharge A/C system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.

WIPERS AND WASHERS
84-2 DESCRIPTION AND OPERATION
Front wiper components
1Linkage assembly
2Wiper motor
3Stud plate
4Gasket
5Wheel box 2 off
6Bolt 2 off
7Earth strap
8Cover plate9Bolt 3 off
10Lock washer
11Nut
12Flanged nut 5 off
13Wiper blade 2 off
14Cover
15Nut
16Wiper arm 2 off

WIPERS AND WASHERS
DESCRIPTION AND OPERATION 84-3
Rear wiper components
1Wiper blade
2Washer jet
3Washer
4Seal
5Washer 2 off
6Lock washer 2 off
7Bolt 2 off8Wiper motor
9Nut
10Nut
11Cover
12Wiper arm
13Washer tube

WIPERS AND WASHERS
84-6 DESCRIPTION AND OPERATION
Wipers and washers block diagram

WIPERS AND WASHERS
84-8 DESCRIPTION AND OPERATION
Description
General
All markets have a common wiper system with headlamp powerwash as an option.
The wipers system comprises two front wipers and one rear wiper which are powered by electric motors. A washer
reservoir is located in the front left hand wheel arch and is fitted with two electric pumps. Each pump supplies washer
fluid to either the front or rear screens. On certain models, a third pump can be fitted to operate a headlamp power
wash function. Operation of the front and rear wipers and washers is controlled by the driver using switches located
on a steering column stalk and push button switches on the fascia.
Control of the wipers and washers is achieved by the following components:
lBCU.
lIDM.
lFront wiper relay.
lFront wash/ wipe switch.
lVariable delay switch.
lFront wiper motor assembly.
lFront washer pump motor.
lRear wiper relay.
lRear wiper switch.
lRear washer switch.
lRear wiper motor.
lRear washer pump motor.
Both the Body Control Unit (BCU) and the Intelligent Driver Module (IDM) control the wiper system. The BCU controls
the time delay function of the wiper system and is located below and behind the passenger glovebox. During engine
cranking the BCU prevents wiper functions. Two relays are located in the passenger compartment fusebox. The
relays control the delay operation of the front and rear wipers. The relays are an integral part of the fusebox and
cannot be renewed separately.
Power for the wiper system is supplied by the IDM, which is integral with the passenger fusebox and cannot be
renewed as a component. A serial communication link allows communication between the IDM and the BCU.
The system has diagnostic capabilities through TestBook.
Front wipers
The two front windscreen wipers are operated by a linkage assembly and an electric motor located under the plenum
grill below the windscreen. The linkage and motor assembly is handed for left and right hand drive vehicles. The motor
is an integral part of the linkage and cannot be replaced separately.
The linkage comprises a pressed steel mounting plate which provides for the attachment of a wheel box at each end.
The mounting plate is secured to the bulkhead with flanged nuts which attach to a stud plate located behind the
bulkhead. A link arm is attached to each wheel box by a short link and secured with circlips. The link arm has an
attachment hole centrally located along its length for the electric motor drive link.
The electric motor is mounted in a recess in the bulkhead below a sealed cover plate. The drive spindle of the motor
protrudes through the cover plate and is fitted with a link. The link is attached to a tapered spline on the motor spindle
and is secured with a lock washer and nut. The opposite end of the link is attached to the central attachment point on
the link arm and secured with a circlip.
Each wheel box has a taper splined shaft which allows for the attachment of the wiper arm which is secured with a
washer and nut. The shaft of each wheel box is passed through a rubber sealed aperture in the plenum. The wiper
arm attachment to the splined shaft has a pivot to which the remainder of the arm is attached. The two parts of the
arm are connected by a spring which controls the pressure of the blade on the screen to a predetermined amount.

WIPERS AND WASHERS
DESCRIPTION AND OPERATION 84-11
The dc motor contains two permanent magnets, three brushes and a park switch. The smaller third brush is utilised
for high-speed operation. Attached to the brush pack are 3 capacitors, which minimise radio interference during wiper
operation. A thermal trip switch attached to the brush plate prevents thermal overload of the motor.
The motor incorporates a worm drive gear unit to transfer the rotary motion into a linear motion of the wiper linkage
assembly.
The front wiper motor receives battery voltage from fuse 19 of the passenger compartment fuse box. For low-speed
operation, including intermittent variable delay operation, the battery voltage to move the wiper motor from the park
position passes through the front wiper relay. When the park switch moves to the closed when operating position,
fuse 19 of the passenger compartment fuse box provides battery voltage directly to the wiper motor.
For high-speed operation, including flick wipe, fuse 19 in the passenger compartment fuse box provides the battery
voltage to move the wiper motor from the park position through the front wash/ wipe switch to the front wiper motor.
To achieve high-speed wiper operation, power is supplied to a third brush that provides a closer distance between the
motor poles. Because the poles of the motor are closer together, the motor operates faster.
Rear wiper
The rear wiper is driven directly from an electric motor located inside the tail door. The motor is mounted inside the
tail door with two bolts, lock washers and washers. The motor mounting brackets have rubber inserts to prevent motor
operating noise being transferred to the door structure. The motor spindle is fitted with a seal and protrudes through
a hole in the tail door outer skin panel. The motor spindle is secured to the tail door with a washer and nut.
The motor output spindle has a taper splined shaft which allows for the attachment of the wiper arm which is secured
with a nut. The wiper arm attachment to the splined shaft has a pivot to which the remainder of the arm is attached.
The two parts of the arm are connected by a spring which controls the pressure of the blade on the window to a
predetermined amount.
The wiper blade is attached to the wiper arms with a clip which allows the blade to pivot. The wiper blade comprises
of a number of levers and yokes to which the rubber wiper is attached. The levers and yokes ensure that the pressure
applied by the arm spring is evenly distributed along the full length of the blade. The rubber wiper is held in the yokes
by a pair of stainless steel strips which also contribute to the even distribution of spring pressure along the blade.
Rear wiper switch
The rear wiper switch is a latching pushbutton switch and is located on the right hand side of the instrument pack.
Activating the rear wiper switch provides an earth signal to the BCU. The BCU signals the IDM to energise the rear
wiper relay, which provides battery voltage to the rear wiper motor.