C05C3
Brake Booster Motor A Supply Circuit
Generic fault on brake booster motor A supply circuit. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
Generic fault on brake booster motor A supply circuit. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
Common causes
- high
Supply wiring or fuse fault
One of the most commonly reported causes for this code — check this first.
Typical part cost: $60-660
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 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 C05C3 mean?
C05C3 means "Brake Booster Motor A Supply Circuit". It is a generic OBD-II code that points to a fault in the chassis.
What are the most common causes of C05C3?
supply wiring or fuse fault — 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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