Operation CHARM: Car repair manuals for everyone.

Air Temperature Sensor ( Ambient / Intake ): Testing and Inspection



Diagnosis Of Intake Air Temperature Sensor

A maximum plausible signal check is continuously performed.

The intake air temperature signal may become faulty, due to a wiring interruption, or a short to ground.

If the sensor signal exceeds a threshold a sensor signal max. fault is detected.

In order to detect a faulty temperature sensor signal below the plausible operation limit, additional conditions (e.g. time delay after end-of-start has elapsed, minimum idling time without fuel cutoff) have to be met in order to determine that a working sensor would have to output a higher value, as a result of heat soak from the engine. Otherwise, when below this threshold, a sensor signal fault is detected.

Diagnose of Intake Air Temperature Sensor