P26B0Engine Coolant Bypass Valve B Range/Performance
- 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
- P26B0 covers a valve B that is electrically sound but does not perform: it moves too slowly, stops short of its target or reports a position that does not match the command. No manufacturer publishes criteria for P26B0. The closest public example is GM's logic for the valve A counterpart P26A3 on the 2011 Volt, Type B, which fails the valve when an end-position learn above 50 °C coolant fails or the commanded position is not reached within 15 s. Ford, which defines valve B as its transmission cooling valve, lists only circuit codes for it. Under CARB, an output that can affect emissions needs a functional check where feasible. Sluggish valves from contaminated coolant, worn gears or a weak motor are the expected causes.
- What you may notice
- Check engine light
- Engine or transmission temperature outside its normal band
- Likely causes
- LikelyValve moving slowly due to contaminated or wrong coolant
- PossibleWorn gear train or weak valve motor
- RareLow supply voltage or high resistance in the drive circuit
- 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: €0 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.