Reductant Temperature Sensor B Circuit High
Voltage on the reductant temperature B sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
Affected components
- Reductant temperature sensor b
- Wiring harness
- Ecm
Common causes
- High likelihood: Signal wire shorted to B+
- Medium likelihood: Open sensor
- Low likelihood: Connector pins corroded - high contact resistance
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
- Reduced-power or limp mode may occur
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.