P2CF6Hybrid/EV Battery Pack Coolant Pump B Overspeed/Air in System
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2CF6 reports that battery coolant pump B spins above its commanded speed. Once a centrifugal pump loses its load it accelerates, so the most common explanation is air or a low level in the loop, which the title names directly. Ford shows the pattern on the 2022–2023 F-150 Lightning: under programme 23B09, battery coolant tube assemblies made of the wrong material could leak, and P2B29, the pump A version, could set without any other effect; the remedy was new tubes. Overspeed/dry run (B1) is likewise a separate pump fault category in Ford's 2024 summary. No manufacturer publicly documents P2CF6 for pump B. Bleeding the loop with the prescribed procedure and finding the leak come first; a loose impeller or false speed feedback is rarer. Underspeed is P2CF7, a blocked pump P2CF5.
- What you may notice
- Gurgling or whining from the pump area
- Coolant level in the battery reservoir drops
- MIL or hybrid warning, sometimes without other effect
- Likely causes
- LikelyAir left in the battery loop after service or poor bleeding
- PossibleLeak at a battery coolant tube or joint lowering the level
- RareImpeller slipping on the shaft or broken
- RareFalse speed feedback from the pump electronics
- 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: €50 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.