Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition
Diagnostic trouble code (DTC) ECM-18 or ECM-1C is stored if the heated oxygen sensor (HO2S) pre-heating circuit is short-circuited to ground or voltage, if there is an open-circuit in the circuit or if the resistance in the element is incorrect.

Substitute value
Fuel trim disabled.

Possible source

Signal too high:
- Short-circuit to supply voltage in the signal cable
- Faulty heated oxygen sensor (HO2S).

Signal too low:
- Short-circuit to ground in the signal cable
- Faulty heated oxygen sensor (HO2S).

Signal missing:
- Open-circuit in the signal cable
- Faulty heated oxygen sensor (HO2S)
- Contact resistance and oxidation.

Faulty signal:
- Faulty heated oxygen sensor (HO2S)
- Contact resistance in the terminals.

Fault symptom[s]
- None.