O2 Sensor Pumping Current Trim Circuit Low (Bank 2 Sensor 2)
O2 trim line on bank 2 sensor 2 stuck low — short to ground. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Affected components
- Oxygen sensor
Common causes
- High likelihood: Short to ground
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Harness chafing through insulation
Possible symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.