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P0040

P0040

Diagnostic 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 all short tests in sequence (without Tank tightness).
or
- Lambda control Active
- Driving, at:
- small valve lift (See Actual value A220)
- large valve lift (See Actual value A220)

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