Reductant Level Sensor A Circuit
A general electrical fault is reported on DEF level sensor A — open, shorted, or out of plausibility. Some tanks use multiple level senders to cover irregular tank shapes; this is the primary one.
Affected components
- Reductant level sensor
- Reductant tank
Common causes
- High likelihood: Sender failed — float, swing arm, or rheostat
- Medium likelihood: Harness or connector fault
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.