oil LAND ROVER DISCOVERY 2002 Workshop Manual

AIR CONDITIONING
82-4DESCRIPTION AND OPERATION
Refrigerant system
Schematic of air conditioning system
1Evaporator
2Thermostatic expansion valve
3Low pressure servicing connection
4Outlet to rear A/C system (where fitted)
5Dual pressure switch
6Receiver drier
7Cooling fan
8Condenser
9Compressor10Inlet from rear A/C system (where fitted)
11High pressure servicing connection
12Air flows
aAmbient air
bCooled air
cAmbient air through condenser
13Refrigerant
aLiquid
bVapour
The refrigerant system transfers heat from the vehicle interior to the outside atmosphere to provide the heater
assembly with dehumidified cool air. The system comprises a compressor, condenser, receiver drier, thermostatic
expansion valve and evaporator, joined together by refrigerant lines. The system is a sealed, closed loop, filled with
a charge weight of R134a refrigerant as the heat transfer medium. Oil is added to the refrigerant to lubricate the
internal components of the compressor.

AIR CONDITIONING
82-6DESCRIPTION AND OPERATION
Condenser
1Condenser matrix
2Outlet connection
3Inlet connection
The condenser transfers heat from the refrigerant to the surrounding air.
The condenser is installed immediately in front of the oil coolers. Rubber mounting bushes are used to mount the
condenser to the chassis sidemembers and brackets on the headlamp panels.
Ambient air, passing through the condenser matrix due to ram effect and/or the cooling fan, absorbs heat from the
refrigerant, which changes state from a vapour to a liquid.

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
REFRIGERANT RECOVERY, RECYCLING AND RECHARGING 82-29
REFRIGERANT RECOVERY, RECYCLING AND RECHARGING
Refrigerant recovery, recycling and
recharging
$% 82.30.02
Recovery
1.Remove dust caps from high and low pressure
connectors.
2.Connect high and low pressure hoses to
appropriate connections.
3.Open valves on connectors.
4.Turn valves on refrigerant station to correct
positions.
Operate the refrigerant station in accordance
with the manufacturers instructions.
5.Turn Process switch to correct position.
6.Turn Main switch to 'ON'.
7.Allow station to recover refrigerant from
system.
WARNING: Refrigerant must always be
recycled before re-use to ensure that the
purity of the refrigerant is high enough for
safe use in the air conditioning system.
Recycling should always be carried out with
equipment which is design certified by
Underwriter Laboratory Inc. for compliance
with SAE J1991. Other equipment may not
recycle refrigerant to the required level of
purity.
A R134a Refrigerant Recovery Recycling
Recharging Station must not be used with
any other type of refrigerant.
Refrigerant R134a from domestic and
commercial sources must not be used in
motor vehicle air conditioning systems.
8.Close valves on refrigerant station.
9.Turn Main switch to 'OFF'.
10.Close valves on connectors.
11.Disconnect connectors high and low pressure
hoses from connectors.
12.Fit dust caps to connectors. 13.Open tap at rear of station to drain refrigerant
oil.
14.Measure and record quantity of refrigerant oil
recovered from system.
15.Close tap at rear of station.
Evacuation
WARNING: Servicing must only be carried
out by personnel familiar with both the
vehicle system and the charging and testing
equipment. All operations must be carried
out in a well ventilated area away from open
flame and heat sources.
1.Remove dust caps from high and low pressure
connectors.
2.Connect high and low pressure hoses to
appropriate connections.
3.Open valves on connectors.
4.Turn valves on refrigerant station to correct
positions.
5.Turn Process switch to correct position.
6.Turn Main switch to 'ON'.
7.Allow station to evacuate system.
Recharging
NOTE: When recharging, always make
allowance for refrigerant in the line between the
charging station and the vehicle. This is
calculated at 30 grammes/metre of charging
line. System charge weights are 700
± 25
grammes for front A/C system only and 900
±
25 grammes for combined front and rear A/C
system.
1.Close valves on refrigerant station.
2.Close valve on oil charger.
3.Disconnect yellow hose from refrigerant
station.
4.Remove lid from oil charger.
5.Pour same quantity of refrigerant oil into oil
charger as collected during recovery. If the
following components have been renewed, add
the following additional quantity of lubricating
oil:
lCondenser = 40 cm
3
lEvaporator = 40 cm3
lPipe or hose = 5 cm3/metre
lReceiver/dryer = 15 cm3.
6.Fit lid to oil charger.
7.Connect yellow hose to refrigerant station.
8.Open valve on oil charger.
9.Move pointer on refrigerant gauge to mark
position of refrigerant charge quantity.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Capacities.

AIR CONDITIONING
REPAIRS 82-31
REPAIRS
Compressor - diesel
$% 82.10.20
Remove
1.Remove engine acoustic cover.
2.Depressurise air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
3.Remove auxiliary drive belt.

+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
4.Drain cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
5.Disconnect multiplug from compressor.
6.Remove 2 bolts securing air conditioning pipes
to compressor and discard 'O' rings.
CAUTION: Always fit plugs to open
connections to prevent contamination.
7.Release clips and disconnect top hose from
coolant elbow and heater pipe.
8.Remove 4 bolts securing compressor to
mounting bracket.
9.Remove compressor.Refit
1.Calculate the quantity of refrigerant oil required.

+ GENERAL INFORMATION, Air
Conditioning Compressor Replacement.
2.Position compressor to mounting bracket and
tighten bolts to 25 Nm (18 lbf.ft).
3.Remove caps from compressor and pipe
connections.
4.Clean compressor and pipe connections.
5.Lubricate new 'O'rings with refrigerant oil and
fit to compressor.
6.Position A/C pipes to compressor and tighten
bolts to 10 Nm (7 lbf.ft) .
7.Connect multiplug to compressor.
8.Position top hose and secure with clips.
9.Refill cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
10.Fit auxiliary drive belt.

+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
11.Recharge air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
12.Fit engine acoustic cover.

AIR CONDITIONING
82-32REPAIRS
Compressor - V8
$% 82.10.20
Remove
1.Depressurise air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
2.Remove auxiliary drive belt.

+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
3.Disconnect multiplug from compressor.
4.Remove 2 bolts securing air conditioning pipes
to compressor and discard 'O' rings.
CAUTION: Always fit plugs to open
connections to prevent contamination.
5.Remove 4 bolts securing compressor to
mounting bracket.
6.Remove compressor.Refit
1.Calculate the quantity of refrigerant oil required.

+ GENERAL INFORMATION, Air
Conditioning Compressor Replacement.
2.Clean compressor dowels and dowel holes.
3.Position compressor to mounting bracket and
tighten bolts to 25 Nm (18 lbf.ft).
4.Remove caps from compressor and pipe
connections.
5.Clean compressor and pipe connections.
6.Lubricate new 'O' rings with refrigerant oil and
fit to compressor.
7.Position A/C pipes to compressor and tighten
bolts to 10 Nm (7 lbf.ft).
8.Connect multiplug to compressor.
9.Fit auxiliary drive belt.

+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
10.Recharge air conditioning system.

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

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.

AIR CONDITIONING
REPAIRS 82-37
12.Remove receiver drier from mounting bracket.
13.Remove dual pressure switch from receiver
drier
Refit
1.Fit dual pressure switch to receiver drier and
tighten to 10 Nm (7 lbf.ft).
2.Fit receiver drier to mounting bracket and
tighten clamping bolt.
3.Fit receiver drier assembly to condenser.
4.Fit bolts securing receiver drier mounting
bracket to condenser and tighten to 5 Nm (3.7
lbf.ft).
5.Remove caps from air conditioning pipes and
receiver drier.
6.Remove old 'O' rings from pipes.
7.Fit new 'O' rings to pipes and lubricate with
refrigerant oil.
8.Connect air conditioning pipes to receiver
drier.
9.Fit bolts securing air conditioning pipes to
receiver drier and tighten to 5 Nm (3.7 lbf.ft).
10.Connect multiplug to dual pressure switch.
11.Fit front grille.

+ EXTERIOR FITTINGS, REPAIRS,
Grille - front - up to 03MY.
12.Recharge air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
ECU - air temperature control
$% 82.20.90
Remove
1.Release radio from fascia.

+ IN CAR ENTERTAINMENT,
REPAIRS, Radio cassette player.
2.Working through radio aperture, release control
unit from fascia.
3.Disconnect 3 multiplugs and remove control
unit.
4.Collect bushes from control unit location pegs.
Refit
1.Fit bushes to new control unit.
2.Position control unit and connect multiplugs.
3.Fit control unit to fascia.
4.Fit radio to fascia.

+ IN CAR ENTERTAINMENT,
REPAIRS, Radio cassette player.

AIR CONDITIONING
REPAIRS 82-43
6.Loosen TXV pipe unions, release pipes and
remove TXV.
7.Remove and discard 'O' rings.
Refit
1.Lubricate new 'O' rings with clean refrigerant oil
and fit to TXV pipes.
2.Position TXV, align pipes and tighten unions.
3.Connect sensor and secure with clip.
4.Fit insulation to TXV valve and sensor.
5.Position seat support bracket, fit bolts and
tighten to 24 Nm (18 lbf.ft)
6.Repressurise air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
7.Fit rear lower trim casing .

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
Evaporator - rear
$% 82.26.20
Remove
1.Remove evaporator assembly.

+ AIR CONDITIONING, REPAIRS,
Evaporator and motor assembly - rear.
2.Remove insulation from TXV.
3.Release relay from support bracket.
4.Remove ducting seal.
5.Remove 4 screws securing lower part of
casing, release and remove lower casing.

AIR CONDITIONING
82-44REPAIRS
6.Remove 6 screws and 4 clips securing main
casing and remove top half of casing.
7.Loosen and release evaporator pipes unions,
release pipes and remove evaporator.
8.Remove and discard evaporator pipe 'O' rings.
Refit
1.Lubricate new 'O' rings with clean refrigerant oil
and fit to evaporator pipes
2.Position evaporator, connect pipes and tighten
unions.
3.Position main casing and secure with clips and
screws.
4.Position lower part of casing and secure with
screws.
5.Fit ducting seal
6.Secure relay to support bracket.
7.Fit insulation to TXV.
8.Fit evaporator assembly.

+ AIR CONDITIONING, REPAIRS,
Evaporator and motor assembly - rear.
Evaporator and motor assembly - rear
$% 82.26.21
Remove
1.Depressurise air conditioning system.

+ AIR CONDITIONING, REFRIGERANT
RECOVERY, RECYCLING AND
RECHARGING, Refrigerant recovery,
recycling and recharging.
2. V8 models: Remove 4 clips securing rear
exhaust heat shield and remove heat shield.
3.Remove 2 bolts securing high and low
pressure pipes, release pipes and discard 'O'
rings.
CAUTION: Always fit plugs to open
connections to prevent contamination.
4.Remove 2 bolts securing grommet flange to
body and remove flange.
5.Remove LH rear lower trim casing.

+ INTERIOR TRIM COMPONENTS,
REPAIRS, Trim casing - side - loadspace.
6.Remove 5 bolts securing seat support bracket
and remove bracket.