P0156moderate severityPowertrain
O2 Sensor Circuit Bank 2 Sensor 2
on 2011 Lincoln MKX 3.7L V6 · AWD
What this code means
General malfunction in the downstream O2 sensor on Bank 2.
Symptoms
- Check Engine Light
- Failed emissions
Common causes
- Faulty sensor
- Wiring issue
- Exhaust leak
Diagnostic steps
- Test sensor voltage
- Inspect wiring
- Check for leaks
Repair notes
Replace sensor.
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