C05BA
Brake Booster Motor A Position Sensor Supply Circuit High
Brake Booster Motor A Position Sensor Supply Circuit High: the signal voltage is above the expected range. The electric brake booster generates the braking assist; a motor or sensor fault can reduce or disable power-assisted braking. Safety-relevant.
Brake Booster Motor A Position Sensor Supply Circuit High: the signal voltage is above the expected range. The electric brake booster generates the braking assist; a motor or sensor fault can reduce or disable power-assisted braking. Safety-relevant.
Common causes
- high
Supply wire shorted to battery
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1650
- low
Connector pins corroded - high contact resistance
Less common, but worth ruling out after the more likely causes.
Typical part cost: $220-1650
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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
See related trouble codes
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Frequently asked questions
What does C05BA mean?
C05BA means "Brake Booster Motor A Position Sensor Supply Circuit High". It is a generic OBD-II code that points to a fault in the chassis.
What are the most common causes of C05BA?
supply wire shorted to battery; connector pins corroded - high contact resistance; supply wire pinched against b+ source — 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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