Outside Air Temperature Display

The Ambient Air Temperature (AAT) sensor is hardwired to the PCM  through separate input and return circuits. The PCM  provides a reference voltage to the Ambient Air Temperature (AAT) sensor and monitors the change in voltage resulting from changes in resistance as determined by outside air temperature. The PCM  filters the ambient air temperature input and sends the data to the GWM  through the Medium Speed Controller Area Network (MS-CAN). The GWM  sends the air ambient temperature filtered message to the IPC  over the High Speed Controller Area Network 3 (HS3-CAN).

The PCM  is programmed to update the messaged outside temperature data at different rates depending on several criteria to prevent false temperature displays due to a condition known as heat soaking. Heat soaking is where the outside air temperature is hotter in the location of the Ambient Air Temperature (AAT) sensor than the actual outside air temperature.

When the sensed outside temperature rises, the display updates slowly at varying rates based on vehicle speed. When the sensed outside temperature drops, the display updates more quickly following the drop experienced by the Ambient Air Temperature (AAT) sensor.