P2247: O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1
What to do
Expect worse economy and reduced power. If the sensor is replaced, insist on the exact part number for this engine — these carry an individual calibration in the connector, and a part that merely fits reads plausibly and wrongly.
What this code means
An open reference voltage circuit on the second bank's upstream sensor. The reference mechanism, and the calibration resistor that makes part numbers non-interchangeable, are set out at P2243.
Likely causes
Start here
- Open circuit in sensor wiring · moderate
- Corroded or loose connector · easy
- Failed sensor reference voltage supply · moderate
Less common
- Faulty oxygen sensor · moderate
- Incorrect oxygen sensor fitted · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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