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P0134

P0134

Oxygen sensor ahead of catalytic converter, bank 1 - pump voltage line - open circuit/above limit value/below limit value

Diagnostic conditions
- Battery positive voltage between 10 V and 16 V
- Time after the engine is started longer than 10 seconds

Possible cause of fault
- Electrical fault in pump voltage line
- Oxygen sensor faulty
- DME control module faulty

Affected terminals
DME control module connector A, pin 52, and oxygen sensor connector in front of catalytic converter, bank 1, pin 6

Diagnosis/troubleshooting

NOTE: Do not use contact spray on the oxygen sensor plug connections as this may cause irreparable damage to the wiring (contamination of the oxygen sensor via the reference air channel).

NOTE: Do not confuse oxygen sensor ahead of catalytic converter and oxygen sensor behind catalytic converter as this will cause implausible fault entries.

Distinguishing feature of both sensors:

Oxygen sensor in front of catalytic converter (LSU) has a six-pin connector






Oxygen sensor behind catalytic converter (LSF) has a four-pin connector






NOTE: When selecting the fault code table, note the fault type from the extended fault memory.