Ambient Temperature Sensor: Description
WARNING: This page is about a different car, the 2005 Dodge Stratus and 2005 Chrysler Sebring. 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 monitors the air temperature outside of the vehicle. The ambient air temperature sensor is mounted on the inside of front bumper beam and its data is used by the heating-A/C system to maintain optimum cabin temperature levels. See Fig 1.