P2CF8Engine Coolant Bypass Valve D Control Circuit Driver Current/Temperature Too High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2CF8 is raised by the driver of coolant bypass valve D when it measures excessive current or overheats and protects itself. No manufacturer documents P2CF8 publicly, and the meaning of D varies: Ford's 2020–2025 gasoline summaries define valve D as the cabin heating valve and report only the smart driver's circuit fault P26BD, plus P26BF from 2024, while GM's 2019 and 2025 tables use the D stuck codes P26C0/P26C2 for the engine block rotary valve. The nearest documented logic is GM's P23C6 for valve C: motor overcurrent with a controller-specific limit of 8.1–12.8 A, 2 s within 5 s, Type B. A seized valve or a shorted motor or coil is the usual trigger. Depending on the loop, heater output or engine warm-up is affected.
- What you may notice
- Engine warning lamp
- Cabin heat weak or not adjustable (heater valve)
- Engine warms up abnormally if the valve sits in the engine loop
- Likely causes
- LikelyValve stiff or seized, so the motor or solenoid draws excess current
- PossibleShorted winding in the valve actuator
- PossibleValve wires partly shorted to ground or to each other
- RareOverheated or faulty output stage in the control module
- 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: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.