Ambient Air Temperature Sensor
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The Ambient Air Temperature (AAT) sensor is a Negative Temperature Coefficient (NTC) thermistor installed in the left exterior rear view mirror. The bulb of the sensor is positioned over a hole in the bottom of the mirror casing.
The Powertrain Control Module (PCM) provides the ambient air temperature sensor with a 5V reference voltage and translates the return signal voltage into a temperature. The PCM transmits the temperature on the High Speed (HS) Controller Area Network (CAN) Powertrain bus for use by other systems. The ATCM receives the temperature on the HS CAN Power Mode Zero bus via the Body Control Module/Gateway Module (BCM/GWM).