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Air Conditioning




Air Conditioning


Evaporator Temperature Sensor

The evaporator temperature sensor contains a thermistor which receives a reference voltage from the HVAC module. The thermistor then varies the resistance to the reference voltage based on the evaporator fin temperature. The resulting voltage is interpreted as an evaporator fin temperature reading.

The HVAC module maintains evaporator core temperature and prevents icing of the evaporator core. It does this by switching off the A/C request signal to the instrument cluster when the evaporator temperature sensor reading falls below acceptable levels, and by switching on the A/C request when the evaporator temperature rises above acceptable levels.

The evaporator temperature sensor electrical connector is located outside of the heater core and evaporator core housing near the accelerator pedal, with the sensor pigtail leading into the housing to the sensor probe which is inserted between the evaporator core fins.

The evaporator temperature sensor is not available as a separate component. To install a new evaporator temperature sensor, a new heater core and evaporator core housing must be installed.