OBD-II code · Powertrain (generic, extended)

P208B Reductant Pump A Control Performance/Stuck Off

DEF pump A receives a run command but does not start, or shuts off prematurely — pump performance is below threshold.

Is it safe to drive with P208B?

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

Common causes

  • Most likelyPump motor seized — DEF crystallised inside pump head
  • PossibleMotor brushes worn
  • Less likelyCarbon or debris buildup preventing free movement

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
1–3.5 h
Emissions test
Likely to fail
Parts involved
Reductant Pump

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