P233DFuel Pressure Regulator B Solenoid Supply Voltage Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Where the ECM switches the solenoid of fuel pressure regulator B on both sides, the ground-side line is checked under P2294 to P2296 and the feed from the high-side driver under P233D to P233F. P233D is the open-circuit code for that feed. No manufacturer documents it publicly: GM's 2025 diesel table 25OBDG04A, where regulator B is the rail pressure regulator valve, contains only the low and high codes of this circuit and folds a broken feed into its regulator tests. The basis is therefore CARB's rule that output components be checked for circuit continuity. An open feed leaves the valve without current regardless of command, so the ECM loses its means of setting rail pressure; depending on the system the pressure rises or collapses, typically with reduced power.
- What you may notice
- Check engine light on
- Rail pressure not controllable, reduced power
- Possibly hard starting or stalling
- Likely causes
- LikelySupply wire to the regulator solenoid broken or terminal loose
- PossibleCorrosion at the regulator connector
- PossibleRegulator solenoid winding open
- RareHigh-side driver in the engine control module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.