NOx Sensor Performance Slow Response Low to High Bank 1 Sensor 3
NOx Sensor Performance Slow Response Low to High Bank 1 Sensor 3: the component is electrically intact but its response does not match the command.
Affected components
- Nox sensor b1s3
Common causes
- High likelihood: Sensor element aged
- Low likelihood: Sensor element contaminated by oil, soot or coolant
- Low likelihood: 5V/reference voltage unstable under load
Possible symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
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.