Reductant Level Sensor A/B Correlation
The signals of the reductant level sensors A and B do not correlate within the calibrated tolerance. One sensor drifts or installation offset between channels.
Affected components
- Reductant level sensor a
- Reductant level sensor b
- Scr module
Common causes
- High likelihood: One sensor characteristic drifted
- Medium likelihood: Harness incorrectly swapped between channels
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
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.