Code result
C05D5
Brake Master Cylinder Cut Off Valve
High severity
What it means
Fault on master cylinder cut-off valve — used in brake-by-wire systems to isolate the master cylinder during normal electric boost.
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
Valve stuck or coil failed
highOne of the most commonly reported causes for this code — check this first.
Related help
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