P0161
PowertrainOxygen Sensorlow severityO2 Sensor Heater Circuit Bank 2 Sensor 2
What P0161 Means
Malfunction in the downstream O2 sensor heater on Bank 2.
Symptoms
- Check Engine Light
- Failed emissions
Common Causes
- Faulty heater
- Blown fuse
- Wiring issue
Diagnostic Steps
- Check fuse
- Test heater resistance
- Inspect wiring
Where to start: Replace sensor.
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