1998 JAGUAR X308 valve

Inputs / Outputs
1.1. Engine speed:
Input to the A/CCM from the ECM. Heated windshield and backli ght will be inhibited when engine speed < 50 RPM.
2. 2. Vehicle speed:
Input from the instru ment cluster. Blower speed control to minimise the effects of ram ai r. Road speed compensation is inhibited when maximum
cooling LO, or maximum heating HI, is selected; also inhi bited in defrost mode with airflow set to maximum.
Used to determine the frequency at which the exterior temperature display is updated.
3. 3. Coolant temperature (signal derived from ECM via instrument cluster):
Input from the heater matrix temperature sensor used to control water valve and thus vent temperatures. Used to monitor the temperature of coolant at the heater matrix to assist the control of air outlet temperature. Used to inhibit the blowers when heating is selected and the engine coolant temperature is below 30°C. Is used to provide progressive increase in blower speed up to 60°C. To inhibit the water valve and pump when the coolant temperature is = < 10°C
Sensors and Controls
Solar Sensor

The heater matrix temperature sensor is a thermistor which changes its electrical resistance in response to changes in air
temperature converting a temperature rating to an electrical signal.
The sensor connector is located on the RH SIDE of the air conditioning unit. The sensor bead is located inside the unit down-
stream from the heater matrix and measures the 'post-heater' air temperature, before the air is distribu ted to the cabin The
sensor provides a signal to the A/CCM which adjusts the duty ratio of the water valve to provide the required air
temperature from the heater.
Ambient Temperature Sensor
The sensor is a thermistor which changes its electrical resistance in response to changes in air temperature, converting a
temperature rating to an electrical signal.

The ambient temperature sensor measures exterior air temper ature and is mounted on the crossbeam, in front of the
condenser on the LH side.

The signal from the ambient sensor allo ws the A/CCM to compensate for the ambient conditions and to display the
information on the control panel - updated every four (4) seconds.
Sensor response is 'damped' by the A/CCM and ther efore does not appear to react to temperature chan
ges as quickly as the

other sensors. This feature prevents the effects of sudden changes in air outlet temperatures due to factors such as:
Recirculating air from the engine cooling pack at low vehicle speeds Sudden changes in ambient temperature The effects of water splash
Motorised In-car Aspirator.

An intake grille (mounted on the fascia , outboard of the steering column and below the EOD vent) houses the aspirator
thermister. The remotely mounted motor / fan assembly draws ca bin air through the grille and thus over the thermistor; a
flexible hose connects both components.
The electrical resistance of the thermistor changes in response to variations in air temperatur e, this change being converted
into an electrical signal. The A/CCM uses this signal to adjust the temperature, airflow and air distribution from the air
conditioning unit.
Coolant Temperature Signal.
This signal is supplied to the A/CCM from the instrument cluster, the input being required to:
Provide blower inhibit control , to avoid the system in heat ing mode delivering cold air when the coolant temperature is below 35°C unless DEFROST is selected. To progressively increase the fan speed up to maximum blower speed during warm up control. To assist in the control of the outlet temperature. To avoid possible pump or valve damage ca used by ice particles in the coolant.
Compressor ON Signal.
This signal monitors the compressor relay to confirm the compressor operating state and so provide relevant fault
information.
Servo Motor Control.
Flap position, which directs the flow of air through the system, is controlled by servo motors; these may be driven in either
a clockwise or anti-clockwise direction by signals from the A/ CCM. Motor, thus flap position, is monitored via a feedback
potentiometer which is situated within the motor housing.
Servo motors control the following flaps:

Control Components - Control Components
Diagnosis and Testing
Connector Pin Identity Chart for AC001

Connector Pin Identity Chart for AC002

Pin NumberCircuitCircuit Function
001Compressor ON signal
002Coolant valve
003RH Blower motor relay
004Heated windshield relays (where fitted)
005Heated door mirror relay
006Defrost servomotor (positive)
007Center vent servomotor (positive)
008LH air intake servomotor fre sh / recirculation (positive)
009RH air intake servomotor fresh / recirculation (positive)
010Not used
011Not used
012Foot servomotor (positive)
013Cool air bypass servomotor (positive)
014Not used
015Not used
016LH Blower motor relay
017Coolant pump motor relay
018Heated backlight relay
019Defrost servomotor (negative)
020Center vent servomotor (negative)
021LH air intake servomotor fresh / recirculation (negative)
022RH air intake servomotor fresh / recirculation (negative)
023Not used
024Not used
025Foot servomotor (negative)
026Cool air bypass servomotor (negative)

System Self-test
Other conditions which may exist but will NOT log fault codes:
Associated Faults
System Self-test
Panel Communication Check
The panel communication check veri fies the inputs and outputs from the control panel to the A/CCM.
Actuator Check Procedure
The system self test procedure drives all the actuator moto rs, to check their operation. If an actuator is operating
incorrectly or operating outside of its limi ts then a fault code will be present.
Before commencing with the actuator check procedure, ensure the ca r is operating under normal conditions.
1. 1. Switch ignition OFF.
2. 2. Press and hold the RECIRC and AUTO buttons simult aneously, switch ignition ON and run the engine.
3. 3. All the control panel LEDs and all LCD segments will flas h on and off. Any function LED indicator which does not
flash on / off suggests a fault condition within that area of the panel or, with the LED.
Any LCD element which fails to flash on / off indicates a fault within the display element or panel.
4. 4. Press AUTO
43 Cool air by-pass
motor faultHarness / connector fault
Servo motor seized or sticking
Flap seized or sticking
*
*
*Refer to PDU
*
43 Cool Air by-pass
motor faultHarness / connector fault
Servo motor seized or sticking
Flap seized or sticking
*
*
*Refer to PDU
*
44 Defrost vent motor
faultHarness / connector fault
Servo motor seized or sticking
Flap seized or sticking
*
*
*Refer to PDU
*
45 Centre vent motor
faultHarness / connector fault
Servo motor seized or sticking
Flap seized or sticking
*
*
*Refer to PDU
*
46 Foot vent motor
faultHarness / connector fault
Servo motor seized or sticking
Flap seized or sticking
*
*
*Refer to PDU
*
SymptomPossible SourcesAction
No heatAirlock in system.
*Refer section 303-03 for fill / bleed procedure
*
Heater water pump inoperative
Coolant flow valve stuck closed
*
*Check operation and circuit
*
Faulty engine coolant thermostat
*Renew as required
*
One vent failing to open / closeBroken linkage.
*Renew as required
*
Poor airflowBlower motors - incorrect operation
*Check operation and circuit
*
ItemCheck LEDCondition
IgnitionDefrostIGN input at 12V, check LED is illuminated
AuxiliaryFaceAUX input at 12V, check LED is illuminated
ClockFeet / faceClock input normal, check LED is illuminated
Start inputFootStart input normal, check LED is illuminated
Data outScreen / footData out input normal, check LED is illuminated
Dimmer overrideRecirc.Dimmer override input ON, check LED is illuminated

5.5. Press RECIRC button to instigate actuator check mode.
6. 6. Press FACE to cycle through the actu ator mode conditions 20 to 27.
7. 7. Press the FAN button to restore normal operation with default panel settings, ie AUTO @ 24°C.
Actuator Fault Codes
• NOTE: * The water valve operates on a 6 second pulse, ie 3 seconds ON, 3 seconds OFF.


Outlet
Code Blower Level Centre vent Foot Defrost Cool air by-pass Fresh / Recirc. Compressor Water valve Water pump
200openclosedclosedclosedfreshOFFclosedOFF
211openclosedclosedclosedfreshOFFclosedON
2210openclosedclosedopenhalf openA/C ONclosedON
2317bleedhalf openclosedhalf openhalf openA/C ON6s pulse * ON
2417bleedhalf openclosedclosedrecirc.A/C ON6s pulse * ON
2523closedopenbleedclosedrecirc.A/C ONopenON
2623closedhalf openhalf openclosedrecirc.A/C ONopenON
2731closedclosedopenclosedopenA/C ONopenON

Engine Management Fuse Box

Heelboard Fuse Box - Right hand side
Fuse NoRating
(amps)Circuit
120Adaptive damping
215Intercooler water pump (Supercharger)
325Starter solenoid.
45Engine control module.
510Fuel injectors.
65Transmission control module
7-Not used.
810Air conditioning compressor clutch.
930Throttle motor.
105Engine control module, Park/Neutr al switch, cruise control VSV 1 and 2 (where fitted), EGR valves.
11-Not used.
1210Air flowmeter, VVT solenoids.
13-Not used.
1410HO2S sensor heaters (where fitted ), EVAP valve, ignition coils relay, throttle motor relay, AC
compressor clutch relay, radi ator fans control module, CCV.
1530Windscreen left-hand heater.
165Control module compartment cooling fan.
1730Windscreen right-hand heater.
1810Ignition coils, ignition amplifier.
Fuse NoRating (amps)Circuit
120Left-hand seat control module.
215Door lock relay, door locking actuators.
315Body processor module.
410Door mirror heaters, mirror foldback.
55Radio telephone.
610Air conditioning.
720Body processor module (column motor power).
85Rear window switchpack, passenger door switchpack.
95Passenger seat switchpack.

Wipers and Washers - Windshield Wiper MotorVehicles Built Up To:
10/1997
Removal and Installation
Removal
1. Remove battery cover and disc onnect ground cable from
battery terminal. Refer to 86.15.19.
2. Remove top covers from LH an d RH bulkheads and rear of
engine compartment. Refer to 76.11.33 and 76.11.35.
3. Remove wiper arm and blade as sembly. Refer to 84.15.44.90.
4. Remove plenum cover. Refer to 76.10.01

5. Remove motor harness multiplug from clip, disconnect
multiplug and position harness clear of clip.

6. Slacken and remove nut securi ng wiper spindle to top of
plenum, remove washer and seal and discard seal.

7. Slacken and remove nut securing engine harness main
multiplug to mounting bracke t and position multiplug for
access.
8. Slacken and remove two nuts an d bolts securing purge valve
mounting bracket to bulkhead and position assembly for
access.