Diagnosis of Ambient Air Temperature

Diagnosis of Ambient Air Temperature
This diagnosis compares the measured ambient air temperature to the modeled ambient air temperature, if the enable conditions are set.

The enable conditions are:
- Intake air temperature signal useful
- integrated air mass flow since engine start above threshold
- air mass, engine speed and vehicle speed above threshold constantly

The ambient air temperature signal is taken from CAN. Electronic connection faults cause an max. fault in the ECU.

CAN time-outs or the un useful CAN signal "Tamb." causes a signal fault.

Flow chart Diagnose of Ambient Air Temperature Sensor (plus check)







Flow chart Diagnose of Ambient Air Temperature Sensor (sig check)







Flow chart Diagnose of Ambient Air Temperature Sensor (range fault)