Diagnostic trouble code (DTC) information ECM-120A
Condition
The engine control module (ECM) checks the signal from the intake air temperature (IAT) sensor in the intake manifold. The diagnostic trouble code (DTC) is stored if the engine control module (ECM) detects that the value from the air temperature sensor deviates too much from the values for engine coolant and outside temperature after the engine has been switched off for an extended period.
The diagnostic trouble code (DTC) can be diagnosed at ignition after the engine has been allowed to cool for at least 8 hours.
Substitute Value
- The value for the intake air temperature (IAT) is set at 30 °C.
Possible Source
- Contact resistance in the connector
- Damaged intake air temperature (IAT) sensor (in the mass air flow (MAF) sensor).
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.