All codes/C056A

C056A

Brake Booster Pressure Sensor Power Supply Circuit

High severity

Fault on brake booster pressure sensor power supply circuit. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.

Fault on brake booster pressure sensor power 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

  • Supply wiring fault

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

    high

    Typical part cost: $60-440

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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 C056A mean?

C056A means "Brake Booster Pressure Sensor Power Supply Circuit". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C056A?

supply wiring 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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