temperature JAGUAR XFR 2010 1.G Workshop Manual
Page 1690 of 3039
Published: 11-May-2011
Climate Control - Heating and Ventilation - Component Location
Description and Operation
NOTE: RHD (right-hand drive) vehicle shown, LHD (left-hand drive) vehicle similar.
Component Location
Item Description 1 Ventilation outlet 2 Blower relay (on RJB (rear junction box)) 3 Heater assembly 4 Blower control module 5 Blower 6 ATC (automatic temperature control) module 7 Air inlet duct 8 Auxiliary coolant pump Comments:
All except 3.0L vehicles; 5.0L version shown, 3.0L diesel version similar.
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Climate Control - Heating and Ventilation - Overview
Description and Operation
Overview Published: 11-May-2011
The heating and ventilation system controls the temperature and flow of air supplied to the passenger compartment. The
system is a dual zone automatic system, which can provide different temperature settings for the LH (left-hand) and RH
(right-hand) sides of the passenger compartment.
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Touch screen display (TSD) 6 Integrated control panel 7 Information control module 8 ATC (automatic temperature control) module 9 Face/Feet distribution stepper motor 10 RH (right-hand) temperature blend stepper motor 11 LH (left-hand) temperature blend stepper motor 12 Windshield (defrost) distribution stepper motor 13 Blower control module 14 RJB (rear junction box) 15 Blower
System Operation
Operation of the heating and ventilation system is controlled by the ATC module. Refer to: Control Components (412-01 Climate Control, Description and Operation).
The system can be operated in automatic or manual mode, with temperature settings selected using the switches on the
integrated control panel.
When the engine is running, coolant is constantly circulated through the heater core by the engine coolant pump and the
auxiliary coolant pump. Where fitted, the auxiliary coolant pump is energized by the CJB on receipt of medium speed CAN bus signals from the ATC module. The CJB broadcasts auxiliary coolant pump status over the medium speed CAN bus for use by other vehicle systems.
The blower is supplied with power by the blower relay on the RJB and connected to ground via the blower control module. The blower control module regulates the voltage across the blower motor to control blower speed. The voltage set by the blower
control module is controlled by a PWM (pulse width modulation) signal from the ATC module. The ATC module uses a feedback signal from the blower control module to monitor blower speed.
Refer to: Control Components (412-01 Climate Control, Description and Operation).
Heater Assembly Component Description
The heater assembly controls the temperature and flow of air supplied to the air distribution ducts. The heater assembly is
mounted on the vehicle centerline, between the instrument panel and the engine bulkhead.
The heater assembly consists of a casing that contains an A/C (air conditioning) evaporator, a heater core, two air distribution
control doors and two temperature blend control doors. On 2.7L diesel vehicles, the heater assembly also contains an electric
booster heater.
Refer to: Electric Booster Heater (412-02 Auxiliary Climate Control, Description and Operation).
Mounted on the heater casing are four stepper motors. Each of the stepper motors is connected to either an air distribution
control door or a temperature blend control door.
The A/C evaporator is part of the A/C system. Refer to: Air Conditioning (412-01 Climate Control, Description and Operation).
The heater core provides the heat source to warm the air supplied to the passenger compartment. The heater core is an
aluminum two pass, fin and tube heat exchanger, and is installed across the width of the heater housing. Two aluminum tubes
attached to the heater core extend through the engine bulkhead and connect to the engine cooling system. For additional
information, refer to:
Engine Cooling (303-03A, Description and Operation),
Engine Cooling (303-03B Engine Cooling - V6 3.0L Petrol, Description and Operation), Engine Cooling (303-03C, Description and Operation).
Air Inlet Duct
The air inlet duct connects the fresh air inlet in the engine bulkhead to the heater assembly. The air inlet duct is installed
behind the instrument panel on the passenger side.
The air inlet duct consists of a casing that contains a pollen filter, an air inlet door, a blower and a blower control module. A
recirculation air inlet is incorporated into the casing. A servo motor is mounted on the casing and connected to the air inlet
door, to allow selection between fresh and recirculated air.
Refer to: Control Components (412-01 Climate Control, Description and Operation). The pollen filter is part of the air distribution and filtering system.
Refer to: Air Distribution and Filtering (412-01 Climate Control, Description and Operation).
The blower regulates the volume of air flowing through the air inlet duct to the heater assembly. The blower consists of an
open hub, centrifugal fan and an electric motor.
The blower control module regulates the power supply to the blower motor. The blower control module is installed in the air
Page 1698 of 3039
Published: 11-May-2011
Climate Control - Air Conditioning - System Operation and Component Description
Description and Operation
General System Operation
To accomplish the transfer of heat, refrigerant is circulated around a sealed system, where it passes through two
pressure/temperature regimes. In each of the regimes the refrigerant changes state, during which process maximum heat
absorption or dissipation occurs.
The low pressure/temperature regime is from the thermostatic expansion valve, through the evaporator to the compressor. The
refrigerant decreases in pressure and temperature at the thermostatic expansion valve, then changes state from a liquid to a
vapor in the evaporator to absorb heat.
The high pressure/temperature regime is from the compressor, through the condenser and receiver drier assembly to the
thermostatic expansion valve. The refrigerant increases in pressure and temperature as it passes through the compressor, then
releases heat and changes state from a vapor to a liquid in the condenser.
Operation of the A/C (air conditioning) system is controlled by the ATC (automatic temperature control) module.
Refer to: Control Components (412-01 Climate Control, Description and Operation). The A/C system works in conjunction with: The air distribution and filtering system.
Refer to: Air Distribution and Filtering (412-01 Climate Control, Description and Operation). The heating and ventilation system.
Refer to: Heating and Ventilation (412-01 Climate Control, Description and Operation).
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1 Pressure relief valve 2 Outlet port 3 Inlet port 4 Solenoid valve 5 Electrical connector 6 Pulley The A/C compressor circulates refrigerant around the system by compressing low pressure, low temperature vapor from the evaporator and discharging the resultant high pressure, high temperature vapor to the condenser.
The A/C compressor is a permanently engaged variable displacement unit which is driven by the engine accessory drive belt. To protect the system from excessive pressure, a pressure relief valve is installed in the outlet side of the A/C compressor. The pressure relief valve vents excess pressure into the engine compartment.
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Thermostatic Expansion Valve
Item Description 1 Metering valve 2 Housing 3 Diaphragm 4 Temperature sensor 5 Outlet passage from evaporator 6 Inlet passage to evaporator The thermostatic expansion valve meters the flow of refrigerant into the evaporator, to match the refrigerant flow with the
heat load of the air passing through the evaporator.
The thermostatic expansion valve is a block type valve located behind the heater assembly, and attached to the inlet and
outlet ports of the evaporator. The thermostatic expansion valve consists of an aluminium housing containing inlet and outlet
passages. A ball and spring metering valve is installed in the inlet passage and a temperature sensor is installed in the outlet
passage. The temperature sensor consists of a temperature sensitive tube connected to a diaphragm. The bottom end of the
temperature sensitive tube acts on the ball of the metering valve. Pressure on top of the diaphragm is controlled by the
evaporator outlet temperature conducted through the temperature sensitive tube. The bottom of the diaphragm senses
evaporator outlet pressure.
Liquid refrigerant flows through the metering valve into the evaporator. The restriction across the metering valve reduces the
pressure and temperature of the refrigerant. The restriction also changes the liquid stream of refrigerant into a fine spray, to
improve the evaporation process. As the refrigerant passes through the evaporator, it absorbs heat from the air flowing through
the evaporator. The increase in temperature causes the refrigerant to vaporise and increase in pressure.
The temperature and pressure of the refrigerant leaving the evaporator acts on the diaphragm and temperature sensitive tube,
which regulate the metering valve opening and so control the volume of refrigerant flowing through the evaporator. The warmer
the air flowing through the evaporator, the more heat available to evaporate refrigerant and thus the greater volume of
refrigerant allowed through the metering valve. www.JagDocs.com
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pressure/temperature regimes. Larger diameter pipes are installed in the low pressure/temperature regime and smaller
diameter pipes are installed in the high pressure/temperature regime.
Low and high pressure charging connections are incorporated into the refrigerant lines for system servicing.
Page 1704 of 3039
Climate Control - Control Components - Component Location
Description and Operation
NOTE: RHD (right-hand drive) vehicle shown, LHD (left-hand drive) vehicle similar.
Component Location Published: 29-May-2014
Item Description 1 Pollution sensor Comments:
where fitted 2 Sunload sensor 3 Ambient air temperature sensor 4 Windshield (Defrost) distribution stepper motor 5 Evaporator temperature sensor
Page 1705 of 3039
7 LH (left-hand) temperature blend stepper motor 8 Control switches 9 Humidity and temperature sensor 10 Air inlet servo motor 11 Blower 12 ATC (automatic temperature control) module 13 Blower control module 14 Face/Feet distribution stepper motor 15 Refrigerant pressure sensor 16 A/C (air conditioning) compressor solenoid valve
Page 1706 of 3039
Climate Control - Control Components - Overview
Description and Operation
Overview Published: 11-May-2011
The climate control system is controlled by the ATC (automatic temperature control) module. It controls the heating and
ventilation system and the A/C (air conditioning) system to regulate the temperature, volume and distribution of air into the
passenger compartment. The system is a fully automatic dual zone system capable of maintaining individual temperature
levels selected for the LH (left-hand) and RH (right-hand) sides of the passenger compartment, up to a maximum differential
of approximately 3 ºC (5.4 ºF). Manual overrides for the system include inlet air source, blower speed and air distribution.
These selections can be made using either the soft switches on the home and climate control screens of the touch screen
display (TSD), or the switches on the integrated control panel.
The ATC module also controls: The rear window heater.
The windshield heater (where fitted).
The exterior mirror heaters.
The seat heaters (where fitted).
The steering wheel heater.
TSD Home Screen
TSD Climate Control Screen