Diagnosis of Ambient Air Temperature

Diagnosis of Ambient Air Temperature

This diagnosis compares the measured ambient air temperature to the modelled ambient air temperature, if the enable conditions are set.

The enable conditions are:
- Intake are 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 DME.

CAN timeouts or unuseful CAN signal Tamb cause a sig fault.

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






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






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