U061ALost Communication With Reductant Level Sensor B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- Some SCR tanks carry more than one level measurement, for example a second sensing element, a second tank chamber or a separate sender; which point counts as B is the manufacturer's choice, and no public document assigns it. U061A is stored when the controller stops receiving usable digital frames from level sensor B while sensor A may still report normally. That pattern points to the wiring branch, connector or electronics of the second sensor rather than to the network as a whole. Supplier sensors such as SSI's ultrasonic DEF unit put level and temperature on a J1939 CAN link, so a dead sensor looks to the controller like any missing node. Circuit-type faults of the same sensor are P21A8 to P21AC. Expect a warning lamp and a DEF reading that no longer matches the tank.
- What you may notice
- Check engine light or DEF system warning
- DEF level shown wrongly or not at all
- Likely causes
- LikelyOpen or chafed wire in the branch that feeds only level sensor B
- PossibleWater or corrosion in the connector of sensor B
- PossibleLevel sensor B electronics failed
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.