P25B1Fuel Level Sensor B Stuck
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P25B1 points at the second fuel level sender, the one found in the passive half of a saddle tank or in an additional tank. Its reading no longer changes in step with the fuel actually burned. Ford applies the same consumption comparison as for sender A, with mismatch limits between 25 % and 60 % depending on the frozen level, and the 2024 summary maps this fault to P2065 with failure type 2A. A frozen B reading is not always the sender's fault: if the jet pump that pulls fuel across from the passive side stops working, that half really does stay full while the other empties, which looks the same to the module. The averaged gauge value then drifts away from the true content and the range estimate becomes unreliable. Ford's 2014 Boss 302S list gives P25B1 the lamp; GM uses P2066 for a stuck second sender instead.
- What you may notice
- Gauge reading too high or barely falling as the tank empties
- Engine stalls from fuel starvation with an apparently quarter-full tank
- Check engine lamp on
- Likely causes
- LikelyFloat of sender B jammed or resistor track worn
- PossibleJet pump or its line no longer drawing fuel from the passive tank half
- RareBlocked or kinked transfer line between the tank chambers
- 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: €120 – €650
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.