NOx Sensor Heater Sense Circuit Range/Performance (Bank 2)
The heater feedback (sense) line on the bank 2 NOx sensor reports values outside the expected window — heating is happening but the temperature does not match the model.
Affected components
- Nox sensor b2
- Nox sensor heater
Common causes
- High likelihood: Heater element ageing, resistance drift
- Medium likelihood: Sensor module failed
- Low likelihood: Sensor element aged beyond calibration window
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
- A drive cycle may be required after repair
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.