P2248: O2 Sensor Reference Voltage Performance Bank 2 Sensor 1
What to do
Expect worse economy. If an oxygen sensor was fitted on this bank recently, verify the part number before anything else — a sensor that fits but carries a different calibration causes this and cannot be found by testing wiring.
What this code means
The bank 2 reference voltage is present but drifted or inconsistent with the calibration expected. As at P2244, a recently fitted sensor of the wrong part number is the leading cause, and a supply or ground with developed resistance is the leading alternative.
Likely causes
Start here
- Incorrect oxygen sensor fitted · moderate
- High resistance in sensor wiring · moderate
- Poor module ground connection · moderate
Less common
- Faulty oxygen sensor · moderate
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Community experience
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