Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information ECM-120D

Condition




The engine control module (ECM) checks the signal from the intake air temperature (IAT) sensor under two different driving conditions. First at a high air flow with vehicle speed, then at idle speed and a stationary vehicle.
The diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers that the temperature difference at these two measurement points is implausibly similar.

Substitute value
- The value for the intake air temperature (IAT) is set at 30 °C.

Possible source
- Contact resistance in the connectors
- Damaged intake air temperature (IAT) sensor.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.