Sensor-Ambient Air Temperature: Operation

WARNING: This page is about a different car, the 2005 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.

The ambient air temperature sensor is a variable resistor that operates on a ground circuit and a 5-volt reference signal circuit sent by the front control module (FCM) through a two-wire lead and connector of the vehicle wire harness. The ambient air temperature sensor changes its internal resistance in response to changes in the outside air temperature, which either increases or decreases the reference signal voltage read by the FCM. The FCM converts and broadcasts the sensor data over the controller area network (CAN) B bus, where it is read by the A/C-heater control and other various vehicle control modules.

The ambient air temperature sensor is diagnosed using the scan tool. Refer to appropriate Engine ELECTRICAL DIAGNOSTICS article for more information.

The ambient air temperature sensor cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.