Master Cylinder Piston Position Higher Than Expected
Master cylinder piston position higher than expected — typically too much pedal travel for the commanded brake pressure.
Affected components
- Master cylinder
Common causes
- High likelihood: Air in brake system or fluid leak
Possible symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Diagnostic notes
- The malfunction indicator lamp may illuminate
- A drive cycle may be required after repair
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.