Cabin Temperature Sensor / Switch: Description and Operation

IN-CAR TEMPERATURE SENSOR

ATC In-Car Temperature Sensor:

The in-car temperature sensor is used in the automatic temperature control (ATC) heating-A/C system only. The in-car temperature sensor returns electrical signals to the body control module (BCM). The in-car temperature sensor is made up of two parts. One part is the in-car sensor aspirator motor assembly, and the second part is a temperature thermistor. The in-car sensor aspirator motor assembly attaches to the back of the A/C-heater control. This assembly has a small fan and a motor which draws air from the passenger compartment through the intake on the front of the A/C-heater control and past the in-car sensor thermistor which is located inside of the A/C-heater control.

In-Car Sensor Aspirator Motor Operation:

Air is drawn from the passenger compartment by the aspirator motor, and flows over the in-car temperature sensor thermistor. The thermistor changes resistance with air temperature. The BCM measures this resistance and calculates the temperature of the air drawn into the A/C-heater control. The ATC system then makes adjustments to maintain the optimum passenger compartment comfort. Refer to the In-Car Sensor Aspirator Motor Operation table for when the aspirator motor is operating.

The in-car temperature sensor thermistor and aspirator motor are part of the A/C-heater control and cannot serviced separately. If faulty or damaged, the A/C-heater control must be replaced.