O2 Sensor Reference Voltage Circuit Open Bank 2 Sensor 1
Code P2247 indicates an open circuit in the reference voltage supply to the oxygen sensor located before the catalytic converter on Bank 2 (the side of the engine not containing cylinder #1). The oxygen sensor requires a stable 5-volt reference signal from the engine control module (ECM) to function properly. When this circuit is open, the sensor cannot provide accurate air-fuel ratio readings, leading to improper fuel trim adjustments and potential drivability issues.
01. Most Common Causes
- Open or broken wire in the sensor reference voltage circuit
- Corroded or damaged connector at the oxygen sensor
- Faulty oxygen sensor (Bank 2 Sensor 1)
- Blown fuse or damaged ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Poor fuel economy
- Rough idle or hesitation during acceleration
- Failed emissions test
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm code P2247 and check for related codes.
Step 2: Visually inspect the wiring and connector for Bank 2 Sensor 1 for damage, corrosion, or loose connections.
Step 3: With the key on, engine off, use a multimeter to check for 5 volts at the sensor connector reference voltage pin. If no voltage, trace the circuit back to the ECM.
Step 4: If voltage is present, test the sensor ground and signal circuits. Replace the sensor if all circuits check out but the code persists.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code as it can cause poor fuel economy, reduced engine performance, and potential damage to the catalytic converter over time.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, which may include replacing the oxygen sensor or repairing wiring. Parts cost around $30-$80 for the sensor, plus labor.