P25BEAlternative Fuel Disable 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
- P25BE concerns the output with which the engine controller tells an alternative fuel system, usually a CNG or LPG installation, to stop gas operation, for example after a fault, with an empty gas tank or while the engine warms up. The code reports an open circuit or a driver fault on this control line, so the command may no longer reach the gas controller or its shut-off valves. GM describes bi-fuel vehicles such as the Impala with the LFR engine, where one ECM runs both fuel systems and switches to the healthy one if a delivery problem appears; LPG retrofits often add a separate gas controller. No manufacturer documents P25BE publicly. CARB treats such a vehicle as alternate-fueled only while it burns the gas fuel. The vehicle normally keeps running on gasoline.
- What you may notice
- Vehicle stays on gasoline or will not switch to gas
- Fuel mode indicator flashes or shows a system fault
- Check engine lamp
- Likely causes
- LikelyOpen control wire between engine controller and gas system
- PossiblePoor splice or connector in a retrofit gas installation
- PossibleOpen coil in a gas disable relay
- RareOutput driver in the engine controller defective
- 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: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.