Powertrain, generic (extended)

P233F Fuel Pressure Regulator B Solenoid Supply Voltage Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P233F is set when the feed line of the fuel pressure regulator B solenoid carries voltage even though the ECM has its high-side driver switched off. GM's 2025 diesel table 25OBDG04A describes this test for the rail pressure regulator valve: in the off state the voltage across the driver should be large; if it is low, the line is fed from elsewhere, as if tied to power through less than half an ohm. As with the ground short, 61 failures in 122 samples of 6.25 ms decide, and the code is Type A. A permanently powered feed means the valve can only be controlled via the low side, or is energised continuously if that side is also faulty, so rail pressure may drift from target. Typical findings are a harness touching a battery feed or a damaged connector. P233E is the low counterpart.

Likely causes

Regulator supply wire touching a battery or ignition feed
Bent or bridged pins in the regulator connector
High-side driver in the engine control module stuck on

Symptoms

  • Check engine light on in the first trip
  • Rail pressure too high or unstable
  • Reduced engine power possible

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–700
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel pressure regulator bengine control modulewiring harness

Related codes

P233DP233EP2296P2293P00CA

References: gsi.ext.gm.com, law.cornell.edu.