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DME (DFI)

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).
- 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 tests [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