P0040

P0040

Diagnosis information - DME (DFI)

Oxygen sensors ahead of catalytic converter interchanged

NOTE: Do not use contact spray on the oxygen sensor's plug connections as this will result in 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
- Perform short test [Oxygen sensor active test]

or (if no short test is possible):
- Lambda control active
- Driving with large and small valve lift

Possible fault causes
- Oxygen sensors ahead of cat. conv. interchanged