P0156
PowertrainOxygen Sensormoderate severityO2 Sensor Circuit Bank 2 Sensor 2
What P0156 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
Where to start: Replace sensor.
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