P25F1Vacuum Pump Control Circuit B High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P25F1 marks a high reading on the vacuum pump's second (B) control circuit: the module sees voltage on the switched side when it should be low, for example because the line is shorted to battery voltage, the relay contacts have welded together or the pump has lost its ground. In the welded-relay case the pump keeps running after it has been switched off, which wears it out and drains the battery. No manufacturer documents P25F1 publicly. Ford's hybrid summary checks the comparable circuit A against a 1.3 to 5.0 V window with the relay open, a pattern that would also catch a supply that is stuck on. CARB 13 CCR 1968.2 requires electrical outputs to be checked for circuit faults. The opposite fault is P25F0, and P25EE is the open circuit. Drivers may hear the pump running constantly.
- What you may notice
- Vacuum pump running constantly, even with the vehicle switched off
- Discharged 12 V battery
- Warning lamp on
- Likely causes
- LikelyPump relay contacts welded closed
- PossibleFeedback or supply line shorted to battery voltage
- RareLost ground connection at the pump
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €20 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.