P2272: O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 2
What to do
The car will usually drive normally. Ask whether the two rear sensors can be swapped between banks as a test — if the fault follows the sensor it is the sensor, and if it stays on this side it is the exhaust or wiring. And do not accept a converter diagnosis on this bank until this is resolved.
What this code means
The stuck-lean condition of P2270, on the post-catalyst sensor of the second bank. The catalyst monitor for that bank is unreliable until it is fixed, with the same consequence: a converter diagnosis on this side rests on a reading that is not valid.
The bank-swap test described at P2197 works here too and is worth asking for, since the two rear sensors are usually the same part. If the stuck reading follows the sensor to the other bank, the sensor is faulty; if it stays, the exhaust or wiring on this side is.
Likely causes
Start here
- Faulty oxygen sensor · moderate
- Damaged wiring harness · moderate
- Exhaust leak before the sensor · moderate
Less common
- Contaminated oxygen sensor element · 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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