All codes/C05D5

C05D5

Brake Master Cylinder Cut Off Valve

High severity

Fault on master cylinder cut-off valve — used in brake-by-wire systems to isolate the master cylinder during normal electric boost.

Fault on master cylinder cut-off valve — used in brake-by-wire systems to isolate the master cylinder during normal electric boost.

Common causes

  • Valve stuck or coil failed

    One of the most commonly reported causes for this code — check this first.

    high

    Typical part cost: $440-2750

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does C05D5 mean?

C05D5 means "Brake Master Cylinder Cut Off Valve". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C05D5?

valve stuck or coil failed — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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