P2245: O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1
What to do
Expect worse economy and reduced power. Ask what other sensors are reporting faults. A shorted reference line pulls down everything sharing that supply, so several sensors reporting at once is one wiring fault rather than several failed parts.
What this code means
The reference voltage circuit reads below its valid range, normally a short to ground. The module protects the supply by shutting it down, which is why a single shorted reference line can take out every sensor sharing it — the argument at P0641, and the reason to check what else is faulted before assuming this sensor is the problem.
Likely causes
Start here
- Wiring shorted to ground · moderate
- Failed sensor reference voltage supply · moderate
- Faulty oxygen sensor · moderate
Less common
- Melted wiring against the exhaust · moderate
- Corroded or loose connector · easy
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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