Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition
The control module receives information from the heated oxygen sensor (HO2S) about fuel / air mixture. If the fuel / air mixture deviates from lambda=1, the short-term fuel trim will compensate for this by adjusting the injection interval so that lambda=1 is achieved. When the short-term fuel trim makes an adjustment, the long term fuel trim (lambda) will also be adjusted. A diagnostic trouble code (DTC) is stored when fuel trim has reached an upper limit (lean limit) or a lower limit (rich limit).

Substitute value
Fuel trim disabled.

Possible source

Rich limit:
- Contact resistance in the terminals
- High fuel pressure
- Leaking injectors
- Contaminated oil
- Defective heated oxygen sensor (HO2S).

Lean limit:
- Contact resistance in the terminals
- Low fuel pressure
- Air leakage in the intake system
- Leakage in the exhaust system
- Defective heated oxygen sensor (HO2S).

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