P2627O2 Sensor Pumping Current Trim Circuit Low (Bank 1 Sensor 1)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2627 marks a trim signal below its plausible range at the first wide-band probe of bank 1. On Ford petrol engines with NTK probes the interface chip sets it when the resistor line (RL) is open or touches ground; Bosch-equipped Fords do not use it. Honda-built 3.5 L V6 engines in GM's 2005 tables read a label resistor instead and log P2627 when its voltage stays above 4.7 V for 5 s, so the naming follows the resistor value rather than the voltage. On GM diesels the code covers the oxygen signal of the NOx sensor behind the turbine: the 2020 table fails readings below -4 percent in 200 of 250 samples, type B. GM's PIP5468D for 2017-18 Silverado and Sierra with the 6.6 L L5P links P2627 to loose charge-air ducts. Open trim is P2626, high is P2628, bank 2 low is P2630.
- What you may notice
- Check engine light
- Further oxygen or NOx sensor codes stored at the same time
- On diesels possibly boost or aftertreatment codes and reduced power
- Likely causes
- LikelyTrim/resistor line open or chafed to ground between probe and engine module
- PossibleWide-band probe or NOx sensor internally faulty
- PossibleLoose or leaking charge-air ducts on diesel engines (GM L5P)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.