Ambient Air Temperature Sensor

WARNING: This page is about a different variant/trim than selected.

NOTE: Some variation in the illustration may occur, but the essential information is always correct.

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

The Ambient Air Temperature (AAT) sensor is a NTC type sensor. The AAT sensor allows the PCM to monitor the temperature of the air around the vehicle.

The PCM uses the AAT sensor input along with other in-vehicle temperature sensors to control:

Vehicles interior temperature.
Engine coolant temperature using the electric cooling fan.

The AAT sensor is installed in the left door mirror, with the bulb of the sensor positioned over a hole in the bottom of the door mirror cover.

The PCM supplies the sensor with a 5V reference voltage and a ground, and translates the return signal voltage into a temperature value.

If there is a fault with the AAT sensor, the PCM calculates the ambient air temperature. The PCM uses the temperature input of the MAFT sensor to calculate the AAT. If the AAT sensor and the temperature inputs of the MAFT sensor are all faulty, the PCM adopts a default AAT of 25°C (77°F).