P233D: Fuel Pressure Regulator B Solenoid Supply Voltage Control Circuit Open
The supply line that powers the solenoid of fuel pressure regulator B is open. Without supply the regulator cannot operate and the ECU cannot maintain rail pressure on this stage; sets when the controller sees no current flow even with the solenoid commanded on.
What P233D means
P233D is a generic OBD-II powertrain code in the fuel & air group. In plain English: the computer found an electrical fault in that circuit: an open, short or bad connection, or a failed component.
- Check engine light
- Usually on
- Emissions-related
- Yes — can fail inspection
- Limp mode possible
- Not typical
- Drive cycle to clear
- Not required
Get it fixed
Post this code once and get quotes from local mechanics. Free to post.
Makes the repair and parts links below specific to your car. Kept in this browser only.
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
Common causes
- 01Supply line open or relay defectiveMost likely
- 02Fuse for regulator B supply blownPossible
- 03Pin pushed back out of connector bodyLess likely
Can I drive with P233D?
Usually yes, for a short time.
The car will often drive normally, but get it diagnosed soon. Left alone it can raise fuel use and emissions and will fail an OBD inspection. If you notice rough running, warning lights flashing, overheating or a burning smell, stop driving.
Why we rate it moderate
- Turns on the check engine light
- Emissions-related: will usually fail an OBD inspection
Severity is our rule-based rating from the code’s flags in OBDex and the system it affects, not an inspection of your car. If the check engine light is flashing, or you notice overheating, low oil pressure, or brake or steering problems, stop driving and get help.
How to diagnose P233D
- 1
Confirm the code and save freeze-frame data
Read the codes with an OBD-II scan tool and note every code, not just P233D. Save the freeze-frame data (speed, load, temperature when the fault set) before clearing anything; it tells you when the fault happens.
- 2
Fix other faults first
If other codes are stored, start with power-supply, sensor-circuit and communication codes. They can cause this code as a side effect.
- 3
Test the circuit
Inspect the wiring and connector at the fuel pressure regulator b and regulator b supply relay for damage, corrosion or chafing. With a multimeter, check supply voltage, ground and signal against the specifications in the service manual for your vehicle.
- 4
Test the likely causes in order
Start with the most likely cause and work down: Supply line open or relay defective; fuse for regulator B supply blown; pin pushed back out of connector body. Test before replacing parts.
- 5
Check for recalls and service bulletins
Look up recalls for your exact vehicle with its VIN, and ask a dealer about technical service bulletins (TSBs). Manufacturers sometimes issue software updates or extended warranties for known faults.
- 6
Clear the code and verify the repair
After the repair, clear the code and drive the car under the conditions in the freeze-frame data to confirm it does not return.
P233D repair cost estimate
Estimate, not a quote. Labor times are typical ranges for this code from OBDex, and $125/hr is an assumed rate. Shop rates and labor times vary by vehicle and region. Diagnosis time may be billed separately.
- DIY difficulty
- Moderate
- Good DIY job?
- Yes, with a scan tool
Needs a scan tool and some experience with testing.
Parts and systems involved
- Fuel pressure regulator B
- Regulator B supply relay
- Fuel rail
P233D FAQ
What does P233D mean?
P233D means “Fuel Pressure Regulator B Solenoid Supply Voltage Control Circuit Open”. The supply line that powers the solenoid of fuel pressure regulator B is open. Without supply the regulator cannot operate and the ECU cannot maintain rail pressure on this stage; sets when the controller sees no current flow even with the solenoid commanded on.
Is P233D serious? Can I keep driving?
We rate P233D as moderate severity. Usually yes, for a short time. The car will often drive normally, but get it diagnosed soon. Left alone it can raise fuel use and emissions and will fail an OBD inspection. If you notice rough running, warning lights flashing, overheating or a burning smell, stop driving.
What causes P233D?
The most common causes, from most to least likely: Supply line open or relay defective; Fuse for regulator B supply blown; Pin pushed back out of connector body. Test before replacing parts, because several causes can set the same code.
How much does it cost to fix P233D?
Typical labor is about $75–$190 at an assumed $125/hour shop rate, plus parts. That is an estimate, not a quote: labor times and rates vary by vehicle and region, and diagnosis may be billed separately.
Can I fix P233D myself?
DIY difficulty is moderate. Many owners can handle it with a scan tool, a multimeter and basic hand tools. Always confirm the cause before buying parts.
Will P233D clear itself?
If the fault was intermittent, the warning may go off once the computer stops seeing it, but the code stays in memory. Fix the cause; clearing the code alone doesn’t repair anything.