Air Conditioning Evaporator Temperature Sensor

Air Conditioning Evaporative Temperature (ACET) sensor senses evaporator air discharge temperature. ACET sensor is a thermistor device in which resistance changes with temperature. Electrical resistance of a thermistor decreases as temperature increases, and increases as temperature decreases. PCM sources a low current 5 volts on ACET circuit. With SIG RTN also connected to ACET sensor, varying resistance affects voltage drop across sensor terminals. As A/C evaporator air temperature changes, varying resistance of ACET sensor changes voltage PCM detects. ACET sensor is used to more accurately control A/C clutch cycling, improving defrost/demist performance, and reduce A/C clutch cycling.