P0040

O2 sensors upstream TWC : Plug connections of the O2 sensors are wrongly connected. (P0040)


Possible cause:

- Check assignment of plug connections to O2 sensors.
Affected functions:

- Engine diagnosis
- Exhaust system

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Test 1: Plug connections of the O2 sensors are wrongly connected.

1. Plug connections of the O2 sensors are wrongly connected.
Possible cause and remedy

- The connectors of the O2 sensors upstream of the catalytic converter are swapped.
End of test