OBD-II code · Powertrain (generic, extended)

P249D Closed Loop Reductant Injection Control At Limit Flow Too Low

With reductant injection running closed-loop the controller drives the dosing valve to maximum opening but cannot reach the required AdBlue flow.

Is it safe to drive with P249D?

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

Common causes

  • Most likelyReductant pump pressure low

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
1.5–5 h
Emissions test
Likely to fail
Parts involved
Reductant Injector, Reductant Pump

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