OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

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.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / 3B

Possible causes

  • Control line shorted to ground high
  • Regulator solenoid shorted internally medium
  • Connector pins corroded - high contact resistance low

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

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–450 €
  • Estimated time: 0.6–2 h
  • Component: fuel pressure regulator c
  • Component: fuel rail
  • MIL / check engine light
  • emissions-relevant

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication