P2C64
O2 Sensor Pumping Current Trim Circuit High Bank 1 Sensor 3
The wide-band oxygen sensor on bank 1 sensor 3 reports a pumping current trim circuit high condition. Lambda regulation accuracy is impaired.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Common causes
Ordered by how often each turns out to be the cause.
- Trim wire shorted to B+Common
- Open pump cell trimPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Oxygen Sensor B1s3
- Wiring Harness
- ECM
P2C64 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.