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Ambient Temperature Sensor / Switch HVAC: Description and Operation

This sensor will inform the ATC system of the ambient temperature outside the vehicle. This sensor is used by the ATC system to adjust blower speed, temperature offsets, evaporator temperatures and mode control. If this sensor fails the ATC system will use the battery temperature information as a back up.

NOTE: The ambient sensor is not serviceable and must be replaced if found to be defective.

CIRCUIT OPERATION
The ambient temperature sensor is located outside the vehicle on the radiator closure panel.

Power for the sensor is supplied from the Body Control Module (BCM) on circuit G31.

Circuit C57 is the sensor return and is spliced with the other sensors in the system.