1999 LAND ROVER DISCOVERY Workshop Manual

HEATING AND VENTILATION
80-28REPAIRS
Resistor pack - power resistor A/C
$% 80.20.17
Remove
1.Remove 4 studs securing toe board and
remove toe board.
2.Remove 4 screws securing glove box, release
catch and remove glove box. 3.Disconnect multiplug from resistor.
4.Remove screws securing resistor, release and
remove resistor.
Refit
1.Position resistor and secure with screw.
2.Connect multiplug to resistor.
3.Position glove box, fit and tighten screws.
4.Position toe board and secure with studs.

HEATING AND VENTILATION
REPAIRS 80-29
Heater matrix
$% 80.20.29
Remove
1.Remove heater assembly.

+ HEATING AND VENTILATION,
REPAIRS, Heater assembly - models with
air conditioning.
2.Remove 2 screws securing coolant pipe
saddles and remove saddles.
3.Loosen screws securing coolant pipes to
matrix, release clamps and remove coolant
pipes.
4.Remove and discard 'O' rings.
5.Remove heater matrix.
Refit
1.Position heater matrix, using new 'O' rings fit
coolant pipes and align clamps.
2.Fit saddle clamps and secure with screws
3.Tighten coolant pipe clamp screws.
4.Fit heater assembly.

+ HEATING AND VENTILATION,
REPAIRS, Heater assembly - models with
air conditioning.
Pipe - Heater - Feed
$% 80.25.07
Remove
1.Remove heater return pipe.

+ HEATING AND VENTILATION,
REPAIRS, Pipe - Heater - Return.
2.Release clip securing heater feed hose to
heater feed pipe and disconnect hose from
pipe.
3.Remove nut securing heater feed pipe to
plenum chamber.
4.Press quick release connector and release
heater feed pipe from plenum chamber.
5.Remove and discard 'O' ring from pipe.
Refit
1.Fit new 'O' ring to heater feed pipe and lubricate
with castor oil.
2.Secure heater feed pipe to plenum chamber.
3.Fit and tighten nut securing heater feed pipe to
plenum chamber.
4.Connect heater feed hose to heater feed pipe
and secure with clip.
5.Fit heater return pipe.

+ HEATING AND VENTILATION,
REPAIRS, Pipe - Heater - Return.
M80 0435
23
4

HEATING AND VENTILATION
80-30REPAIRS
Pipe - Heater - Return
$% 80.25.12
Remove
1.Drain engine coolant.

+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.
2.Release clip securing heater return hose to
heater return pipe and disconnect hose from
pipe.
3.Remove bolt securing heater return pipe to
heater feed pipe.
4.Release clips securing engine harness and
vacuum pipe to heater return pipe.
5.Remove bolt securing heater return pipe to
cylinder head.
6.Release clip securing engine coolant hose to
heater return pipe.
7.Release engine coolant hose from heater
return pipe and collect pipe.Refit
1.Connect engine coolant hose to heater return
pipe and secure with clip.
2.Position heater return pipe to cylinder block and
secure with bolt.
3.Secure engine harness and vacuum pipe to
heater return pipe and secure with clips.
4.Fit and tighten bolt securing heater return pipe
to heater feed pipe.
5.Connect heater return hose to heater return
pipe and secure with clip.
6.Refill engine coolant.

+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.
M80 0437
M80 0438
4
46
7
5

HEATING AND VENTILATION
REPAIRS 80-31
Fuel burning heater - (FBH) - Td5
$% 80.40.01.99
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery earth lead.
3.Clamp feed and return coolant hoses at FBH.
4.Position container to collect spillage.
5.Release clips, disconnect coolant feed and
return hoses from FBH.
CAUTION: Before disconnecting or
removing components, ensure the
immediate area around joint faces and
connections are clean. Plug open
connections to prevent contamination.
6.Disconnect 2 multiplugs from FBH.7.Position container to collect spillage and
disconnect quick release fuel pipe from FBH.
CAUTION: Before disconnecting any part of
the fuel system, it is imperative that all dust,
dirt and debris is removed from around
components to prevent ingress of foreign
matter into fuel system.
8.Remove Torx bolt securing FBH to bulkhead
mounting bracket.
9.Release and remove FBH.
10.Collect locating bushes from pegs.
Refit
1.Fit bushes to pegs.
2.Align FBH to pegs, fit Torx bolt and tighten to 25
Nm (18 lbf.ft).
3.Clean quick release connection and fit fuel pipe
to FBH.
4.Connect multiplugs to FBH.
5.Connect coolant hoses to FBH and secure with
clips.
6.Release clamps from hoses.
7.Connect battery earth lead.
8.Fit and secure battery cover.
9.Top-up cooling system.

+ MAINTENANCE, PROCEDURES,
Cooling system.

AIR CONDITIONING
DESCRIPTION AND OPERATION 82-1
AIR CONDITIONING DESCRIPTION AND OPERAT ION
A/C refrigerant system component
layout
Diesel installation shown, V8 similar
1Evaporator and thermostatic expansion valve
2High pressure servicing connection
3To rear A/C system (where fitted)
4Low pressure servicing connection5Refrigerant lines
6Receiver drier
7Condenser
8Compressor

AIR CONDITIONING
82-2DESCRIPTION AND OPERATION
A/C control system component layout
RH drive shown, LH drive similar
1Air temperature control ECU
2Heater coolant temperature sensor
3Evaporator temperature sensor
4Dual pressure switch5Ambient temperature sensor
6Sunlight sensor
7In-car temperature sensor

AIR CONDITIONING
DESCRIPTION AND OPERATION 82-3
Description
General
The air conditioning system controls the temperature, distribution and volume of air supplied to the vehicle interior to
provide a comfortable cabin environment. The system is electronically controlled and features automatic and manual
modes of operation, with separate temperature control of the LH and RH air outlets. The automatic modes provide
optimum control of the system under most ambient conditions and require no manual intervention. The manual modes
allow individual functions of automatic operation to be overridden, to accommodate personal preferences.
The air conditioning system consists of a refrigerant system, a heater assembly and a control system. It also uses the
same air inlet duct and distribution ducts as the Heating and Ventilation system on non air conditioned vehicles.

+ HEATING AND VENTILATION, DESCRIPTION AND OPERATION, Description.
Fresh or recirculated inlet air flows into the heater assembly from the blower in the air inlet duct. In the heater
assembly, the air is cooled and/or heated, depending on the selected cabin temperature and ambient conditions, then
directed to selected air outlets.
On vehicles with rear air conditioning, additional cooling is provided by recirculating air through a second evaporator
and distributing it to outlets in the roof.

+ AIR CONDITIONING, DESCRIPTION AND OPERATION, Description.