B10DFABS master cylinder isolation valve calibration lost
- Ford code · ABS / stability control
- Lights a warning lamp
- How the car detects it
- The ABS module has lost, or never matched, the calibration data for the valve that isolates the brake master cylinder. Ford sees it as an internal ABS module fault or a calibration mismatch between the ABS module and the hydraulic unit: the code is cleared (on the Fiesta after running the valve calibration routines with a scan tool) and, if it returns, the ABS module/HCU assembly is replaced. Ford's ABS module and hydraulic unit (HCU) are serviced as one assembly. While the fault is active, ABS and stability control may be switched off; normal braking still works.
- What you may notice
- ABS and stability control warning lights
- Likely causes
- PossibleCalibration mismatch between ABS module and hydraulic unit
- RareInternal fault of the ABS module
- Sources
Backed by at least two independent sources.
From Obdaryn's Ford pack, exactly as the app shows it, with the public sources above. Guidance only; confirm with a workshop.