OBD-II code · Powertrain (generic, extended)

P223A Reductant Heater E Control Circuit

Reductant Heater E Control Circuit: the control circuit has an electrical fault. The reductant (DEF/AdBlue) heater keeps the urea fluid from freezing; a fault can impair SCR dosing in cold conditions.

Is it safe to drive with P223A?

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

Common causes

  • Most likelyHeater winding or wiring fault

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)

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.7–3 h
Emissions test
Likely to fail
Parts involved
Reductant Line Heater E

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