P0155

P0155

Diagnosis information - DME (DFI)

Heater circuit, oxygen sensor ahead of cat. converter, bank 2

NOTE: Do not use contact spray on the oxygen sensor plug connections, as this will cause irreparable damage to the lines (blockage of reference air duct).

NOTE: Do not interchange the oxygen sensor ahead of catalytic converter with the sensor behind the catalytic converter as this will result in implausible fault entries.

Diagnostic conditions
- Time after engine starts more than 10 seconds
- Oxygen sensor heater control active
- Lambda control active
- No driver fault of oxygen sensor stored

Possible fault causes
- Contact resistance between DME control unit and oxygen sensor heater ahead of catalytic converter, bank 2
- Contact resistance between fuse and oxygen sensor heater ahead of catalytic converter, bank 2
- High resistance shunt to signal line
- Oxygen sensor faulty