The P2247: O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1 refers to an issue where the reference voltage circuit for the oxygen (O2) sensor in Bank 2 Sensor 1 is open or disconnected. This means there is no continuity in the circuit, which can prevent the sensor from functioning properly. This fault may be caused by a broken wire, faulty O2 sensor, or damaged connector, leading to incorrect data being provided to the engine control module, which can affect engine performance and emissions.
P2247 – Quick Overview
Code | Information |
---|---|
Meaning | P2247: O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1 |
Is it serious? | Yes, as an open circuit in the reference voltage can lead to incorrect sensor readings, affecting air-fuel ratio adjustments, reducing efficiency, and increasing emissions. |
Possible causes | – Open circuit in O2 sensor reference voltage for Bank 2 Sensor 1 – Faulty O2 sensor – Wiring issues – Connector problems |
How to diagnose? | – Inspect the O2 sensor reference voltage circuit for continuity – Test the O2 sensor for proper operation – Check wiring and connectors for faults |
P2247 Meaning
The P2247: O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1 code indicates that the reference voltage circuit for the O2 sensor on Bank 2 Sensor 1 is open or disconnected. This means that the sensor is not receiving the necessary reference voltage, which is critical for it to properly measure the oxygen content in the exhaust gases. Without this voltage, the sensor cannot send correct data to the engine control unit, affecting the fuel-air mixture and ultimately impacting engine performance and emissions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to determine if there are other related codes. Additional codes may provide further context, indicating if this is an isolated issue or part of a broader electrical problem. | OBD-II Scanner |
Inspect the O2 Sensor Reference Voltage Circuit for Continuity | Use a multimeter to test for continuity in the reference voltage circuit for Bank 2 Sensor 1. An open circuit indicates a broken wire or disconnected component that needs to be repaired. Trace the wiring and ensure there is proper continuity throughout. | Multimeter, Vehicle Service Manual |
Test the O2 Sensor for Proper Operation | Use a diagnostic tool to test the O2 sensor itself to ensure it is functioning correctly. If the sensor is found to be faulty or not responding to the reference voltage, it will need to be replaced. | Diagnostic Scanner, Multimeter |
Inspect Wiring and Connectors for Faults | Visually inspect the wiring and connectors for Bank 2 Sensor 1. Look for signs of damage such as broken wires, corrosion, or disconnected connectors that could lead to an open circuit. Repair or replace any damaged wiring or connectors. | Flashlight, Safety Gloves |
Check Sensor Connector Condition | Carefully inspect the sensor connector to ensure all pins are properly aligned and there is no corrosion present. Poor connectivity can lead to an open circuit condition. Ensure the connector is securely attached. | Flashlight |
Clear the Code and Test Drive | After making any necessary repairs, use an OBD-II scanner to clear the fault code. Conduct a test drive to verify that the O2 sensor is receiving the correct reference voltage and is functioning as expected. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure that the P2247 code has not returned. If the code reappears, additional diagnostic efforts will be needed to identify the underlying issue. | OBD-II Scanner |

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