O2 Sensor Signals Swapped Bank 2 Sensor 1 and Sensor 2
The pre- and post-catalyst lambda signals on bank 2 are swapped - the upstream sensor responds like a downstream sensor and vice versa. Typically the harness was reversed during a sensor change.
Affected components
- Oxygen sensor b2s1
- Oxygen sensor b2s2
Common causes
- High likelihood: Harness swapped during repair
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.