P1171 – HO2S2 Heater Control (Bank 2 Sensor 2, Nissan)
Description
The ECM detected a malfunction in the heater circuit of the downstream O2 sensor on Bank 2.
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View Recommended ScannersSymptoms
- Poor fuel economy
- Slow closed-loop operation
- Check engine light
Causes
- Faulty O2 sensor heater
- Blown fuse
- Damaged wiring
- Connector corrosion
Diagnosis
- Test heater resistance
- Inspect wiring
- Check fuses
- Scan live data
Repair
- Replace O2 sensor
- Repair wiring
- Replace fuse
- Clean connectors
