Diagnostic trouble code (DTC) information
WARNING: This page is about a different car, the 2004 Volvo S40, 2003 Volvo S40, 2002 Volvo S40, 2001 Volvo S40, and 2000 Volvo S40. However, it is still accessible from the selected car via links, so may be relevant.
Condition
The rear heated oxygen sensor (HO2S) signal is checked when the control module carries out a three-way catalytic converter (TWC) diagnostic. A diagnostic trouble code (DTC) is stored if the rear heated oxygen sensor (HO2S) signal is not within the range permissible for three-way catalytic converter (TWC) diagnostics. Diagnostic trouble code (DTC) ECM-29 is stored if the signal from the heated oxygen sensor (HO2S) is faulty.
Substitute Value
- Fuel trim disabled
- Three-way catalytic converter (TWC) diagnostic disabled.
Possible Source
- Contact resistance in the terminals
- Leakage in the exhaust system
- Defective rear heated oxygen sensor (HO2S).
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.