P2626
O2 Sensor Pumping Current Trim Circuit/Open Bank 1 Sensor 1
The ECU detects an open in the pumping current trim circuit of the wide-band oxygen sensor on bank 1 sensor 1. Without trim correction, the lambda value reported by the sensor is not accurate.
- 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 openCommon
- Internal sensor faultPossible
- Pin pushed back out of connector bodyLess likely
Parts involved
- Oxygen Sensor Wideband
- Oxygen Sensor Trim Wiring
P2626 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.