Air Temperature Sensor ( Ambient / Intake ): Description and Operation

An NTC sensor mounted in the intake manifold provides the intake air temperature input to the MS41.1 control module. It functions the same as the NTC sensor for engine temperature.

The air temperature input is continuously monitored as part of the OBD II emission requirements. The parameters for monitoring include:

- Upper and lower voltage values
- Open circuits

If a malfunction occurs with the air temperature input, the control module will switch to a stored replacement value (FAIL-SAFE) for emergency running. The fault will be stored in memory and the Check Engine Lamp will illuminate when the OBD II criteria is satisfied.