HVAC Climate Control System: Other Ford Escape II

Thermal Protection Switch (Hybrid Only)

Under high A/C load conditions, the A/C compressor temperature may get hot enough to trigger the compressor thermal protection switch which will disengage the A/C compressor clutch. The thermal protection switch is located in the A/C compressor housing, near the discharge port and is wired in series with the A/C clutch field coil. When refrigerant discharge temperatures heat the switch to 115°C (239°F), the switch will open and disengage the compressor, but no PCM DTCs will be set. The switch will close once the temperature cools to approximately 105°C (221°F). If the switch were to stick open, it would remain open at room temperature.

A/C Condenser

The A/C condenser is an aluminum fin-and-micro-channel design heat exchanger located in front of the vehicle radiator. It cools compressed refrigerant gas by allowing air to pass over fins and tubes to extract heat and by condensing gas to liquid refrigerant as it is cooled.

On 2.5L or 3.0L (4V) vehicles equipped with an automatic transmission, the top portion of the condenser is partitioned from the refrigerant system and is used for transmission fluid cooling.

Evaporator Core

Note. A second (auxiliary) evaporator core is used for HVTB cooling on hybrid vehicles. For information concerning the auxiliary evaporator core, refer to AUXILIARY CLIMATE CONTROL - HYBRID .

The evaporator core is an aluminum plate/fin-type and is located in the heater core and evaporator core housing. A mixture of liquid refrigerant and oil enters the bottom of the evaporator core through the evaporator core inlet tube and continues out of the evaporator core through the evaporator core outlet tube as a vapor. During A/C compressor operation, airflow from the blower motor is cooled and dehumidified as it flows through the evaporator core fins.

Thermostatic Expansion Valve (TXV)

Note. A second (auxiliary) TXV is used for High Voltage Traction Battery (HVTB) cooling on hybrid vehicles. For information concerning the auxiliary TXV, refer to AUXILIARY CLIMATE CONTROL - HYBRID .

The TXV is located at the evaporator core inlet and outlet tubes at the dash panel at the rear of the engine compartment. The TXV provides a restriction to the flow of refrigerant from the high-pressure side of the refrigerant system and separates the low-pressure and high-pressure sides of the refrigerant system. Refrigerant entering and exiting the evaporator core passes through the TXV through 2 separate flow paths. An internal temperature sensing bulb senses the temperature of the refrigerant flowing out of the evaporator core and adjusts an internal pin-type valve to meter the refrigerant flow into the evaporator core. The internal pin-type valve decreases the amount of refrigerant entering the evaporator core at lower temperatures and increases the amount of refrigerant entering the evaporator core at higher temperatures.

Receiver/Drier

Note. Installation of a new receiver/drier is not required when repairing the A/C system, except when there is physical evidence of contamination from a failed A/C compressor or damage to the receiver/drier. Damage to the receiver/drier includes leaks, physical damage to the receiver/drier shell or desiccant, or moisture contamination. Moisture contamination results only from a complete loss of refrigerant, and equalization of the refrigerant system pressure with atmospheric pressure for a period longer than one hour. If even a slight amount of positive refrigerant pressure is present in the refrigerant system before repairs are carried out, a new receiver/drier should not be installed.

The receiver/drier is mounted to the right of the radiator support for 2.5L or 3.0L (4V) vehicles, or at the RH shock tower for hybrid vehicles. It stores high-pressure liquid after it leaves the condenser core. A desiccant cartridge mounted inside the receiver/drier removes any retained moisture from the refrigerant.

Evaporator Discharge Air Temperature Sensor

Note. A second (auxiliary) evaporator discharge air temperature sensor is used for the auxiliary evaporator core on hybrid vehicles. For information concerning the auxiliary evaporator discharge air temperature sensor, refer to AUXILIARY CLIMATE CONTROL - HYBRID .

The evaporator discharge air temperature sensor contains a thermistor. The resistance of this thermistor varies by a specific amount based on the evaporator discharge air temperature. The HVAC module measures a voltage ratio between the reference voltage it supplies to the sensor and the sensor return voltage to determine this resistance and the associated discharge air temperature.

The evaporator discharge air temperature sensor maintains evaporator core temperature and prevents icing of the evaporator core. It does this by signaling the HVAC module to switch off the A/C request signal to the instrument cluster on 2.5L or 3.0L (4V) vehicles, or signaling the PCM to cycle the A/C compressor off when the evaporator discharge air temperature sensor reading falls below acceptable levels. The A/C request or A/C compressor will be switched back on when the evaporator temperature rises above acceptable levels.

On hybrid vehicles, the A/C compressor will continue to run and the passenger zone valve will be closed by the PCM if the evaporator discharge air temperature sensor is reading a temperature below acceptable levels, but the TBCM is requesting A/C operation for HVTB cooling. This allows continued refrigerant flow to the auxiliary evaporator core while allowing the front (main) evaporator core to warm to acceptable levels.

The evaporator discharge air temperature sensor is located on the heater core and evaporator core housing behind the glove compartment.

A/C Pressure Transducer (2.5L or 3.0L [4V] Only)

The A/C pressure transducer monitors the compressor discharge pressure and communicates with the PCM. The PCM will interrupt A/C compressor operation in the event that the A/C pressure transducer indicates high system discharge pressures. It is also used to sense low charge conditions. If the pressure is below a predetermined value for a given ambient temperature, the PCM will not allow the clutch to engage.

The A/C pressure transducer is located on the receiver/drier. It is not necessary to recover the refrigerant before removing the A/C pressure transducer.

Scheme 224

ITEM DESCRIPTION

The dual-function pressure switch is located on the receiver/drier and includes 2 separate sets of contacts that are opened at 2 different pressures.

The first set of contacts in the dual-function pressure switch is used to interrupt A/C compressor operation in the event of excessively high discharge pressure in the high-pressure side of the refrigerant system. The PCM monitors the first set of contacts in the dual-function pressure switch in-series with the low-charge protection switch. When the contacts are open, the PCM will disengage the A/C compressor clutch.

The second set of contacts in the dual-function pressure switch is used by the PCM to engage the high-speed cooling fan. When the A/C pressure rises above a preset level, the second set of contacts will close and the high-speed cooling fan will be engaged.

The dual-function pressure switch is installed on a Schrader-type valve core fitting on the receiver/drier. It is not necessary to recover the refrigerant to remove the dual-function pressure switch.

Scheme 225

ITEM DESCRIPTION

The low-charge protection switch is installed on the evaporator outlet line to cycle the A/C compressor off in the event of a low refrigerant charge. The PCM monitors the low-charge protection switch in-series with the dual-function pressure switch. When the low-side pressure drops below acceptable levels, the low-charge protection switch contacts open. When the low-charge protection switch contacts are open, the PCM will disengage the A/C compressor clutch.

The low-charge protection switch is installed on a Schrader-type valve core fitting on the evaporator outlet line. It is not necessary to recover the refrigerant to remove the low-charge protection switch.

Passenger Zone Valve (Hybrid Only)

The passenger zone valve is a solenoid-type valve used on hybrid vehicles to isolate the front (main) evaporator core from the refrigerant system when the A/C compressor is operating for HVTB cooling and A/C operation has not been selected for the passenger compartment. When A/C operation has been selected for the passenger compartment, the passenger zone valve will also be closed to prevent freezing of the front evaporator core if the front evaporator discharge air temperature sensor indicates that the front evaporator temperature has fallen below acceptable levels, while the auxiliary evaporator discharge air temperature sensor is reading within acceptable levels. This is done to prevent the A/C compressor from having to be cycled off when HVTB cooling is still required.

When voltage is applied to the passenger zone valve, it will be in the open state. When voltage is removed, the passenger zone valve will be in the closed state.

The passenger zone valve will only be in either the fully open or the fully closed state and cannot be partially opened.

The passenger zone valve is mounted at the top of the RH shock tower.

Battery Zone Valve (Hybrid Only)

The battery zone valve is a solenoid-type valve used by the PCM on hybrid vehicles to isolate the auxiliary evaporator core from the refrigerant system, when the A/C compressor is operating for passenger compartment cooling and A/C operation has not been requested for HVTB cooling. When A/C operation is requested for HVTB cooling, the battery zone valve will also be closed to prevent freezing of the auxiliary evaporator core if the auxiliary evaporator discharge air temperature sensor indicates that the auxiliary evaporator temperature has fallen below acceptable levels, while the front (main) evaporator discharge air temperature sensor is reading within acceptable levels. This is done to prevent the A/C compressor from having to be cycled off when passenger compartment cooling is still required.

The battery zone valve will periodically be briefly opened during front (main) A/C operation for system maintenance. When A/C operation is not requested, the battery zone valve is closed.

When voltage is applied to the battery zone valve, it will be in the open state. When voltage is removed, the battery zone valve will be in the closed state. The battery zone valve will only be in the fully open or the fully closed state and cannot be partially opened.

The battery zone valve is mounted to the bottom of the auxiliary climate control housing. Refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS - HYBRID .

Service Gauge Port Valves

The high-pressure service gauge port valve is located on the receiver/drier inlet line.

The low-pressure service gauge port valve is located on the evaporator outlet line.

Note. Different valve cores are used for different engine applications. Use only the valve core listed in the Ford Master Parts Catalog for the vehicle and fitting being serviced.

Scheme 226

ITEM DESCRIPTION

The fitting is an integral part of the refrigerant line or component.

1. Special couplings are required for both the high-side and low-side service gauge ports.
2. A very small amount of leakage will always be detectable around the Schrader-type valve with the service gauge port valve cap removed, and is considered normal. A new Schrader-type valve core can be installed if the seal leaks excessively.
3. The service gauge port valve caps are used as primary seals in the refrigerant system to prevent leakage through the Schrader-type valves from reaching the atmosphere. Always install and tighten the A/C service gauge port valve caps to the correct torque after they are removed.

Refrigerant System Dye

Fluorescent refrigerant system dye is added to the refrigerant system at the factory to assist in refrigerant system leak diagnosis using a Rotunda-approved ultraviolet blacklight. It is not necessary to add additional dye to the refrigerant system before diagnosing leaks, even if a significant amount of refrigerant has been removed from the system. Replacement receiver/driers are shipped with a fluorescent dye "wafer" included in the desiccant cartridge, which will dissolve after approximately 30 minutes of continued A/C operation. It is not necessary to add dye after flushing or filtering the refrigerant system because a new receiver/drier is installed as part of the flushing or filtering procedure. Additional refrigerant system dye should only be added if more than 50 percent of the refrigerant system lubricant capacity has been lost due to a fitting separation or hose rupture. Refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS .

Refrigerant Line Fittings

Note. Use only a plastic or nonmetallic tool for removing O-ring seals and gasket seals from the refrigerant line fittings. Use of a metallic tool will create scratches on the sealing surface of the fitting that can result in refrigerant system leaks.

Whenever a refrigerant line fitting is disconnected, the fitting must be cleaned of any foreign material and new O-ring seals and/or gasket seals must be installed. Use only the O-ring seals and gasket seals specified in the Ford Master Parts Catalog.

If a refrigerant system line fitting must remain disconnected for an extended period of time, it should be capped to avoid contamination of the refrigerant system.

Air Distribution

Note. A cabin air filter is available for this vehicle as a dealer installed accessory. The accessory cabin air filter will be located in the air inlet under the RH side of the cowl panel grille, if installed.

There are 2 sources of air available to the air distribution system

1. Outside air
2. Recirculated air

Recirculated air is always used when the HVAC module is set to the MAX A/C mode on vehicles equipped with Electronic Manual Temperature Control (EMTC) and can be selected in any mode except DEFROST. Vehicles equipped with dual-zone Electronic Automatic Temperature Control (EATC) use recirculated air only when the RECIRC function is selected in any mode other than DEFROST, or when required by the HVAC module in the AUTOMATIC mode.

Air distribution within the vehicle is determined by the airflow mode selected, or by the dual-zone EATC system in the AUTO mode. The air distribution mode on vehicles equipped with dual-zone EATC can be overridden by the driver if desired. Airflow mode control doors are used to direct airflow within the heater core and evaporator core housing. Electric mode door actuators are used to position the airflow mode doors and air inlet mode door.

Vehicles equipped with dual-zone EATC use 2 separate temperature blend doors. This allows individual temperature settings to be selected for the RH and LH air outlets. The airflow mode doors are not partitioned for separate RH and LH airflow positions. Therefore, the airflow mode will always remain similar for the RH and LH sides of the vehicle regardless of the temperatures selected.

Air enters the passenger compartment from the following outlets

1. Instrument panel registers
2. Floor duct outlets
3. Windshield defroster
4. Side window demisters
5. Rear footwell duct
6. Center console registers

Passenger compartment air is exhausted from the vehicle through open windows or body air vents.

Control Components

Two climate control systems are available

1. Electronic Manual Temperature Control (EMTC)
2. Dual-zone Electronic Automatic Temperature Control (EATC)

Refer to the appropriate heading below for information concerning each system.

Electronic Manual Temperature Control (EMTC)

Note. EMTC is not available on hybrid vehicles.

Note. When installing a new HVAC module on vehicles equipped with EMTC, the Programmable Module Installation (PMI) procedure must be carried out to configure the new module to the vehicle. Refer to MODULE CONFIGURATION .

The HVAC module selections include the following

1. Air inlet source (outside or recirculated)
2. Blower motor speed
3. Discharge air temperature (temperature blend)
4. Discharge air location (defrost, panel, floor, panel/floor, defrost/floor)
5. A/C compressor operation
6. Rear window defroster operation
7. Heated seat operation (if equipped)

Control System Inputs

The temperature control selector setting determines air temperature. Movement of the temperature display from COOL (blue) to WARM (red) causes a corresponding movement of the temperature blend door and determines the discharge air temperature that the air distribution system will maintain. The temperature control selector is an integral part of the HVAC module and cannot be installed separately. The temperature selector knob is removable and can be installed separately.

The airflow mode setting determines air discharge location. Depressing each airflow mode selector button causes a corresponding movement of the airflow mode doors and determines the air discharge location. The airflow mode selector buttons are an integral part of the HVAC module and cannot be installed separately.

The A/C request button determines A/C compressor operation, except when the airflow mode selector is in the OFF, MAX A/C or DEFROST mode. The A/C request button is an integral part of the HVAC module and cannot be installed separately.

The recirculated air request button can select recirculated air in any mode except DEFROST, and fresh air in any mode except MAX A/C or OFF. The recirculated air request button is an integral part of the HVAC module and cannot be installed separately.

The rear defog button signals activation of the heated backlight. The rear defog button is an integral part of the HVAC module and cannot be installed separately.

The blower motor speed switch is mounted in the HVAC module and controls blower motor speed by adding or bypassing resistors in the blower motor resistor in all modes except OFF. The blower motor switch knob is removable and can be installed separately.

Control System Outputs

The EMTC system has 4 system outputs.

Blower Motor Speed

The blower motor speed switch varies the blower motor ground circuit resistance by adding or bypassing series resistance in the blower motor resistor. Increased resistance will lower the blower motor speed, and lowered resistance will increase blower motor speed. When the blower motor is in the HI (4) position, the blower motor resistor is bypassed.

The blower motor resistor is located on the heater core and evaporator core housing behind the glove compartment.

Temperature Blend Door Position

The temperature blend door actuator moves the temperature blend door on command from the HVAC module.

The temperature blend door actuator contains a reversible electric motor and a potentiometer. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the HVAC module from the contact wiper indicates the position of the temperature blend door. The HVAC module drives the actuator motor in whichever direction is necessary to make the actuator contact wiper voltage agree with the expected HVAC module value. The expected value is set by the vehicle occupants using the temperature selector knob.

The temperature blend door actuator is mounted to the heater core and evaporator core housing.

Airflow Mode Door Position

The airflow mode door actuator uses a cam and lever assembly to position the airflow mode doors on command from the HVAC module. The mode door actuator contains a reversible electric motor and potentiometer. The potentiometer allows the HVAC module to monitor the position of the airflow mode doors. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the HVAC module from the contact wiper indicates the position of the airflow mode doors. The expected HVAC value is set by the vehicle occupants using the mode selector buttons.

The airflow mode door actuator is mounted to the plenum chamber to the right of the accelerator pedal.

Air Inlet Mode Door Position

The air inlet mode door actuator moves the air inlet door between the fresh and RECIRC positions on command from the HVAC module. The air inlet mode door actuator is driven to, and will automatically stop at, the full RECIRC or full fresh air inlet position and does not require a potentiometer circuit to monitor its position. The airflow mode door does not stop at any point between the RECIRC or fresh air inlet position.

The air inlet mode door actuator is mounted to dash panel side of the air inlet duct.

Electronic Automatic Temperature Control (EATC)

The HVAC module analyzes input from the following major sources

1. Temperature, airflow mode, blower, A/C and RECIRC selection (made by the vehicle occupants)
2. ECON button (hybrid only)
3. In-vehicle temperature sensor (non-hybrid only)
4. In-vehicle temperature and humidity sensor (hybrid only)
5. Ambient temperature sensor
6. Sunload sensor (solar radiation sensor)
7. Evaporator discharge air temperature sensor
8. Vehicle speed
9. Engine Coolant Temperature (ECT)

Using these inputs, the HVAC module determines the correct conditions for the following outputs

1. A/C compressor ON/OFF request
2. Blower motor speed
3. Temperature blend door position
4. Airflow mode door position
5. Air inlet door position

The dual-zone Electronic Automatic Temperature Control (EATC) system has 4 control system inputs.

HVAC Module

The HVAC module provides an interface for the vehicle occupants to control the climate control system, or automatically controls the climate control system in the AUTO mode. The HVAC module uses the Front Display Interface Module (FDIM) for displaying set temperature, airflow direction, blower speed and DTCs. An On-Board Diagnostic (OBD) feature is incorporated to supply the technician with DTCs. These DTCs help direct the technician to the inoperative component.

In-Vehicle Temperature Sensor - Non-Hybrid

The in-vehicle temperature sensor contains a thermistor, which measures the in-vehicle air temperature and sends that reading to the HVAC module. An aspirator hose is connected between the heater core and evaporator core housing and the in-vehicle temperature sensor. The aspirator hose uses airflow through the heater core and evaporator core housing to create a Venturi-type suction to draw in vehicle air through the in-vehicle temperature sensor (across the thermistor).

The in-vehicle temperature sensor is mounted to the RH lower portion of the instrument cluster finish panel.

In-Vehicle Temperature and Humidity Sensor - Hybrid

The in-vehicle temperature and humidity sensor contains 2 thermistors, which separately measure the in-vehicle air temperature and humidity and send those readings to the HVAC module. An aspirator hose and elbow is connected between the heater core and evaporator core housing and the in-vehicle temperature and humidity sensor. The aspirator hose uses airflow from the heater core and evaporator core housing air stream to create a Venturi-type suction to draw in vehicle air through the in-vehicle temperature sensor and across the thermistors.

The in-vehicle temperature and humidity sensor is mounted to the RH lower portion of the instrument cluster finish panel.

Sunload Sensor (Solar Radiation Sensor)

The solar radiation sensor supplies information to the HVAC module indicating sunload strength, and (to an extent) direction. The solar radiation sensor is located on the center of the instrument panel at the base of the windshield.

Ambient Temperature Sensor

The ambient temperature sensor signal is received by the HVAC module and indicates the outside air temperature. The ambient temperature sensor is located in front of the radiator on the bottom of the bumper beam.

The ambient temperature sensor signal is not the sole factor considered by the HVAC module for the outside air temperature display. Therefore, the ambient temperature PID monitored with a scan tool may not exactly match the HVAC module display. For information regarding the HVAC module outside air temperature display, refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS .

The EATC system has 4 control system outputs. When operating in AUTO mode, the control system outputs will be automatically adjusted by the HVAC module.

Note. Each of the 4 control system outputs may be overridden by the passenger if desired.

The blower motor speed control controls the blower motor speed by converting low power signals from the HVAC module to a high-current, variable ground feed for the blower motor. A delay function is used to provide a gradual increase or decrease in blower motor speed under all conditions.

The dual-zone EATC system uses 2 temperature blend door actuators to control 2 separate temperature blend doors. The temperature blend doors independently vary the LH side and RH side temperature settings, as desired. The temperature blend door actuators each contain a reversible electric motor and a potentiometer. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the HVAC module from the contact wiper indicates the position of the temperature blend door. The HVAC module drives the actuator motor in whichever direction is necessary to make the actuator contact wiper voltage agree with the expected HVAC module contact wiper voltage value, as determined by the control algorithm.

The temperature blend door actuators are mounted to the heater core and evaporator core housing.

The airflow mode door actuator uses a cam and lever assembly to position the airflow mode doors on command from the HVAC module. The mode door actuator contains a reversible electric motor and potentiometer. The potentiometer allows the HVAC module to monitor the position of the airflow mode doors. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the HVAC module from the contact wiper indicates the position of the airflow mode doors. The HVAC module drives the actuator motor in whichever direction is necessary to make the actuator contact wiper voltage agree with the expected contact wiper voltage value, as determined by the control algorithm.

The airflow mode door actuator is mounted to the plenum chamber to the right of the accelerator pedal.

Air Inlet Mode Door Actuator

The air inlet mode door actuator moves the air inlet door between the fresh and RECIRC positions on command from the HVAC module. The air inlet mode door actuator is driven to, and will automatically stop at, the full RECIRC or full fresh air inlet position and does not require a potentiometer circuit to monitor its position. The airflow mode door does not stop at any point between the RECIRC or fresh air inlet position.

The air inlet mode door actuator is mounted to dash panel side of the air inlet duct.

Heating and Ventilation

The heating and ventilation system has the following features

1. Controls the temperature and, during A/C operation, reduces the relative humidity of the air inside the vehicle.
2. Delivers heated or cooled air to maintain the vehicle interior temperature and comfort level.
3. Cooling or heating can be adjusted to maintain the desired temperature.
4. Uses a reheat method to provide conditioned auto the passenger compartment.
5. All airflow from the blower motor passes through the A/C evaporator core.
6. Temperature blending is controlled by the temperature blend door(s), which regulate(s) the amount of air that flows through and around the heater core, where it is then mixed and distributed.

Heater Core

The heater core consists of fins and tubes arranged to extract heat from the engine coolant and transfer the heat to air passing through the heater core.

The heater core is located in the heater core and evaporator core housing.

Blower Motor

The blower motor pulls air from the air inlet and forces it into the heater core and evaporator core housing where it is mixed and distributed.

The blower motor is located on the bottom of the heater core and evaporator core housing below the glove compartment.

Heater Core and Evaporator Core Housing

The heater core and evaporator core housing directs airflow from the blower motor through the evaporator core and heater core. All airflow from the blower motor passes through the evaporator core. The airflow is then directed through or around the heater core by the temperature blend door(s). Vehicles equipped with dual-zone Electronic Automatic Temperature Control (EATC) use a partitioned heater core and evaporator core housing with 2 electric actuator-positioned temperature blend doors. This allows for separate temperatures to be selected for the driver and passenger sides of the passenger compartment. Manual systems use a single electric actuator-positioned temperature blend door to direct airflow through or around the heater core.

The heater core and evaporator core housing is mounted to the passenger compartment side of the dash panel.

Auxiliary Coolant Flow Pump (Hybrid Only)

An auxiliary coolant flow pump is used only on hybrid vehicles to improve engine coolant circulation at low engine speeds or when the engine is OFF.

The auxiliary coolant flow pump will be disabled when any of the following conditions are present

1. The climate control module is set to the OFF position.
2. The ambient temperature is above 32°C (90°F).
3. The coolant temperature is less than -10°C (14°F).
4. The engine speed is above 4,000 rpm.

When none of the listed conditions are present, the auxiliary coolant flow pump is controlled by a strategy included in the PCM software. The control strategy monitors the ambient temperature, coolant temperature and engine rpm. As the ambient temperature and/or coolant temperature increase, the auxiliary coolant flow pump will shut down at lower engine speeds. For example, when both the ambient temperature is above 16°C (60°F) and the engine coolant temperature is above 66°C (150°F), the control strategy will shut off the auxiliary coolant flow pump at 2,000 rpm. When both the ambient temperature is above 24°C (75°F) and the engine coolant temperature is above 66°C (150°F), the control strategy will shut off the auxiliary coolant flow pump regardless of engine speed.

To verify auxiliary coolant flow pump operation, allow the vehicle to cool in a cool location. Start the engine and let the engine idle until it shuts down automatically. Select the FLOOR mode on the HVAC module at the highest temperature setting and HI blower speed. If the auxiliary coolant flow pump is inoperative or is not producing adequate coolant flow, the passenger compartment air discharge temperature will quickly decrease and further diagnosis is required. Refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS - HYBRID . If the auxiliary coolant flow pump is operating normally, the passenger compartment air discharge temperature will remain steady, or slowly decrease.

The auxiliary coolant flow pump is mounted on the lower LH side of the cooling fan shroud.

Material

MATERIAL SPECIFICATIONS

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Note. If installing a new Air Conditioning (A/C) compressor due to an internal failure of the old unit, carry out the following procedures to remove contamination from the A/C system. Failure to remove contamination from the A/C system, if present, will result in poor A/C performance and/or damage to the new A/C compressor and other components. If A/C flushing equipment is available, carry out flushing of the A/C system prior to installing a new A/C compressor. For additional information, refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS . If A/C flushing equipment is not available, carry out filtering of the A/C system after a new A/C compressor has been installed. For additional information, refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS . Install a new Thermostatic Expansion Valve (TXV), as directed by the A/C flushing or filtering procedure. Install a new auxiliary TXV, as directed by the A/C flushing or filtering procedure. Install a new passenger zone valve. For additional information, refer to PASSENGER ZONE VALVE . Install a new battery zone valve. For additional information, refer to AUXILIARY CLIMATE CONTROL - HYBRID . Install a new receiver/drier as directed by the A/C flushing or filtering procedure.

Note. Installation of a new receiver/drier is not required when repairing the A/C system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the receiver/drier.

Note. A new A/C compressor may come equipped with an A/C clutch disc and hub, A/C compressor pulley and A/C clutch field coil already installed. If these components are not pre-installed, it will be necessary to transfer these parts from the old A/C compressor to the new compressor prior to installation of the A/C compressor if suitable for reuse.

Scheme 230

1. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to «JACKING & LIFTING»(ref-344051) .
2. Recover the refrigerant. For additional information, refer to «CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS»(ref-344063) .
3. Remove the RH lower engine splash shield.
4. Release the tensioner and remove the drive belt from the A/C compressor pulley.
5. Remove the A/C compressor manifold bolt and disconnect the manifold and tube assembly from the A/C compressor. Discard the O-ring seals. To install, tighten to 20 Nm (177 lb-in).
6. Disconnect the A/C clutch field coil electrical connector.
7. Remove the 4 A/C compressor bolts and the A/C compressor. To install, tighten to 25 Nm (18 lb-ft).
8. To install, reverse the removal procedure. If a new A/C compressor is to be installed, the clutch assembly may need to be transferred from the old unit to the new unit. For additional information, refer to «CLUTCH AND CLUTCH FIELD COIL - HYBRID»(ref-344137-S02801437712009101600000) . Install new O-ring seals. If not filtering the A/C system, lubricate the refrigerant system with the correct amount of clean PAG oil. For additional information, refer to «CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS»(ref-344063) .
9. Evacuate, leak test and charge the refrigerant system. For additional information, refer to «CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS»(ref-344063) .

Scheme 231

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Scheme 235

1. Remove the A/C compressor. For additional information, refer to «AIR CONDITIONING (A/C) COMPRESSOR - HYBRID»(ref-344137-S07688247522009101600000) .
2. Remove the A/C clutch disc and hub nut. Using the Compressor Clutch Holding Tool, hold the A/C clutch disc and hub. Remove the A/C clutch disc and hub nut.
3. Remove the A/C clutch disc and hub.
4. Remove the A/C compressor pulley snap ring.
5. Using the Compressor Pulley Remover, remove the A/C compressor pulley.
6. Remove the A/C clutch field coil snap ring.
7. Remove the A/C clutch field coil. Remove the thermal protection switch bolt and bracket. Detach the thermal protection switch from the A/C compressor.
8. Remove the A/C clutch field coil and thermal protection switch assembly.

MATERIAL SPECIFICATIONS

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MATERIAL SPECIFICATIONS

Scheme 240

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 241

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 242

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 243

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 244

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 245

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 246

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 247

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 248

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 249

ITEM DESCRIPTION

MATERIAL SPECIFICATIONS

Scheme 250

ITEM DESCRIPTION