Code result
C05CF
Brake Master Cylinder Piston Position Sensor B Circuit Range/Performance
High severity
What it means
Brake Master Cylinder Piston Position Sensor B Circuit Range/Performance: the signal is implausible or outside the valid range.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Sensor reading drifted
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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