P2247
O2 Sensor Reference Voltage Circuit/Open (Bank 2 Sensor 1)
Moderateoxygen sensor
Overview
The P2247 diagnostic trouble code indicates a o2 sensor reference voltage circuit/open (bank 2 sensor 1) 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
- Reduced catalytic converter efficiency
- Poor fuel economy
- Check Engine Light (MIL) illuminated
- Black smoke from exhaust
Common Causes
- Faulty O2 sensor heater circuit
- Short or open circuit in sensor wiring
- Faulty PCM (Powertrain Control Module)
- Incorrect sensor installed
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
Chevrolet MalibuFord FusionHyundai ElantraMazda 3
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.