Reductant Injection Air Pressure Sensor B Circuit Range/Performance
The reductant injection air-pressure sensor B reads inside the electrical range but does not match expected behaviour over time or load — slow response or wrong offset.
Affected components
- Reductant air pressure sensor
Common causes
- High likelihood: Sensor drift
- Low likelihood: Sensor element aged beyond calibration window
- Low likelihood: Sensor mounting loose - signal damping
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
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.