Evaporator Temperature Sensor / Switch: Description and Operation

Evaporator Temperature Sensor






This thermistor device changes electrical resistance as a result of temperature variations.

The sensor is positioned next to the evaporator fins and measures air temperature after it has passed through the evaporator. The sensor inputs a signal to the A/CCM which controls the compressor (see table) when the refrigeration system is operating.

The sensor's connector is located on the LH side of the air conditioning unit, in front of the main power connector.

Evaporator Temperature
Signal Compressor State
3°C ON - clutch engaged
2°C 0FF - clutch disengaged

The A/CCM disengages the compressor clutch when the temperature of the air off the evaporator is 2°C or less. This is to prevent the moisture which may collect between the cooling fins of the evaporator from freezing and thus restricting airflow.