P0167
O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)
Lowoxygen sensor
Overview
The P0167 diagnostic trouble code indicates a o2 sensor heater circuit malfunction (bank 2 sensor 3) condition. Oxygen sensors monitor the oxygen content in the exhaust stream and provide feedback to the PCM for precise fuel mixture control. A malfunction in the O2 sensor circuit can result in poor fuel economy, increased emissions, and potential catalytic converter damage.
Symptoms
- Poor fuel economy
- Failed emissions test
- Check Engine Light (MIL) illuminated
- Engine misfiring
Common Causes
- Exhaust leak near the oxygen sensor
- Failed or aging oxygen sensor
- Faulty O2 sensor heater circuit
- Contaminated O2 sensor (oil, coolant, or fuel additives)
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored trouble codes and freeze frame data
- 2Monitor the O2 sensor readings using live data on the scan tool
- 3Inspect the O2 sensor wiring and connector for damage or corrosion
- 4Test the O2 sensor heater circuit with a multimeter
- 5Check for exhaust leaks near the O2 sensor location
Estimated Repair Cost
$100 — $400
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Honda CivicMazda 3Kia ForteToyota Corolla
Related Codes
More Oxygen Sensor Codes
P0030HO2S Heater Control Circuit (Bank 1 Sensor 1)
ModerateP0031HO2S Heater Control Circuit Low (Bank 1 Sensor 1)
ModerateP0032HO2S Heater Control Circuit High (Bank 1 Sensor 1)
ModerateP0036HO2S Heater Control Circuit (Bank 1 Sensor 2)
ModerateP0037HO2S Heater Control Circuit Low (Bank 1 Sensor 2)
LowP0038HO2S Heater Control Circuit High (Bank 1 Sensor 2)
ModerateFrequently Asked Questions
Most O2 sensors should be replaced every 60,000-100,000 miles as preventive maintenance. Heated O2 sensors may last longer, but performance gradually degrades with age.