OBD-II code · Powertrain (generic, extended)

P233B Fuel Pressure Regulator C Control Circuit Low

Same as P233A but with the control line shorted to ground - the ECU measures a low voltage that does not match the commanded duty cycle.

Is it safe to drive with P233B?

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
  • PossibleRegulator solenoid shorted internally
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light on
  • Hard start, no start, or stalling under load
  • Power loss especially at high load or rpm
  • Possible long cranking time

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
Fuel Pressure Regulator C, Fuel Rail

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