P241A — O2 Sensor Signals Swapped Bank 1 Sensor 1 and Sensor 2
The pre- and post-catalyst lambda signals on bank 1 are swapped - the upstream sensor responds like a downstream sensor and vice versa. Typically the harness was reversed during a sensor change.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Oxygen sensor b1s1
- Oxygen sensor b1s2
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- 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
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
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.