O2 Sensor Pumping Current Trim Circuit Open Bank 2 Sensor 1
The P2629 code means the vehicle's onboard diagnostic system has detected: O2 Sensor Pumping Current Trim Circuit Open Bank 2 Sensor 1. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $150 - $500 (parts and labor)
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Common Symptoms
- Check engine light on
- Bank 2 fuel trim abnormal
- Reduced fuel economy
- Possible rough idle
Probable Causes (Ranked by Likelihood)
- Failed bank 2 wideband oxygen sensor Very High
- Open wiring in bank 2 O2 sensor circuit High
- Corroded bank 2 O2 sensor connector Moderate
- ECM bank 2 O2 driver failure Low
Frequently Asked Questions
Why does my V6/V8 have separate bank codes?
V-configuration engines have two exhaust banks. Each bank has its own O2 sensor for independent fuel trim control. Bank 2 is the side that does not contain cylinder 1.
Can I drive with only bank 1 sensor working?
The engine will run but bank 2 will operate in open loop, using default fuel maps instead of sensor feedback. Fuel economy and emissions will suffer.
Should I replace both bank sensors at the same time?
If one sensor has failed from age, the other is likely near end of life too. Replacing both ensures consistent performance and avoids a return trip for the second one.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Check bank 2 O2 sensor connector and wiring
-
Measure sensor heater resistance
-
Test sensor signal response
-
Compare bank 2 fuel trims to bank 1
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Commonly Affected Vehicles
- 2010-2020 Toyota Camry V6
- 2012-2019 Honda Accord V6
- 2008-2018 Ford F-150 V8
- 2011-2020 Chevrolet Silverado V8
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