DESCRIPTION

Fig. 33: Identifying Ambient Air Temperature Sensor

The ambient air temperature sensor is a variable resistor that monitors the air temperature outside of the vehicle.

The ATC system uses the sensor data to maintain optimum cabin temperature levels. The ambient air temperature sensor is mounted inside the front fascia.

OPERATION

The ambient air temperature sensor is a variable resistor that operates on a 5-volt reference signal sent by the Totally Integrated Power Module (TIPM). The ambient air temperature sensor is connected to the TIPM 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 TIPM. The TIPM converts and broadcasts the sensor data over the Controller Area Network (CAN) IHS bus, where it is read by the ATC A/C-heater control, Powertrain Control Module (PCM) and other vehicle control modules.

The ambient air temperature sensor is diagnosed using a scan tool.

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