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P2231



P2231

Oxygen sensor upstream

Diagnostic conditions
- DME control module power supply 10.5 V ... 16 V
- Exhaust temperature < 800 °C (1,472 °F)
- Oxygen sensor temperature > 685 °C (1,265 °F)
- Catalytic converter heating not active
- Secondary air injection not active
- No other oxygen-sensor faults upstream stored

Possible fault causes
- High resistance short circuit to B+ in signal wire
- Heater injection
- Oxygen sensor faulty
- DME control module faulty