U061A
Lost Communication With Reductant Level Sensor B
The vehicle bus reports loss of communication with smart reductant (DEF/AdBlue) level sensor B. Tank-level monitoring switches to a substitute model; refill warnings may be incorrect.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Common causes
Ordered by how often each turns out to be the cause.
- Bus wiring open or shortedCommon
- Module without power or groundPossible
- Module failedPossible
Parts involved
- Reductant Level Sensor B
- Vehicle Bus Wiring
U061A is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.