OBD-II code · Powertrain (generic, extended)

P24DD Reductant Purge Control Valve B Circuit Low

Same as P24DB with the control line shorted to ground. The evaporative system captures fuel vapor from the tank and purges it into intake; leaks or stuck purge valves leak hydrocarbons and cause emissions failures.

Is it safe to drive with P24DD?

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

Common causes

  • Most likelyControl line shorted to ground
  • Less likelyConnector pins corroded - high contact resistance
  • Less likelyHarness chafing through insulation

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
Often, with basic tools
Typical labour
0.6–2 h
Emissions test
Likely to fail
Parts involved
Reductant Purge Valve B

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