OBD-II code · Network

U061C Lost Communication With Reductant Temperature Sensor A

The vehicle bus reports loss of communication with smart reductant (DEF/AdBlue) temperature sensor A. Heater control and freeze protection lose their primary feedback.

Is it safe to drive with U061C?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyBus wiring open or shorted
  • PossibleModule without power or ground
  • PossibleModule failed

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

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.5–3 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Reductant Temp Sensor A, Vehicle Bus Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.