Inside Air Temperature Sensor

WARNING: This page is about a different car, the 2002 Pontiac Aztek and 2002 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

Replacement of the inside air temperature sensor means replacing the HVAC Control Module. The inside air temperature sensor is an integral part of the HVAC Control Module. The HVAC Control Module monitors the passenger compartment inside air temperature through an inside air temperature sensor. When the air is cold, the sensor resistance and the signal voltage are high. When the air is warm, the sensor resistance and the signal voltage are low. The HVAC Control Module requests A/C compressor clutch engagement and controls the air temperature actuator door positions in order to maintain the selected air temperature. The HVAC Control Module sends out a 5-volt reference signal to the inside air temperature sensor over the 5-volt reference circuit. A thermistor varies the reference voltage back to the HVAC Control Module through the low reference circuit.