P0138

P0138

Diagnosis information - DME (DFI)

Oxygen sensor behind catalytic converter, bank 1, above limit value

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
- Engine at operating temperature
- Then drive for 2 min.
- Then engine idling more than 30 seconds

Possible fault causes
- Short circuit to B+ in signal line
- Oxygen sensor faulty (short circuit to B+)