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Fault Family System: Chassis (C-Codes) 37 SAE Codes

Electric Brake Booster Motor Circuit

Diagnostic & Technical Explanation
Code C004C (Brake Booster Motor A Position Sensor Exceeded Learning Limit) sets when the electric brake booster's control module cannot verify correct operation of its internal three-phase drive motor -- a phase (U, V, or W) current or voltage reads outside range, the motor's rotor position sensor disagrees with commanded travel, or the module's internal power driver or current sensor reports a fault. This booster uses a ball-screw driven by the motor instead of engine vacuum to build brake assist, so a fault here can reduce or eliminate power assist even though the hydraulic circuit itself is sound. Because this is a sealed, self-calibrating actuator, most faults trace back to internal motor winding failure, a failed position sensor, or the booster's own control electronics rather than external wiring.

These 37 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 37 times.

Codes in this family (37)

CodeDefinitionRepair coverage
C004CBrake Booster Motor A Position Sensor Exceeded Learning Limit4 ranked fixes
C057FBrake Booster Motor A Phase U-V-W Circuit/Open4 ranked fixes
C0580Brake Booster Motor A Phase U-V-W Circuit Low4 ranked fixes
C0581Brake Booster Motor A Phase U-V-W Circuit High4 ranked fixes
C0582Brake Booster Motor A Phase U-V-W Circuit Range/Performance4 ranked fixes
C0583Brake Booster Motor B Phase U-V-W Circuit/Open4 ranked fixes
C0584Brake Booster Motor B Phase U-V-W Circuit Low4 ranked fixes
C0585Brake Booster Motor B Phase U-V-W Circuit High4 ranked fixes
C0586Brake Booster Motor B Phase U-V-W Circuit Range/Performance4 ranked fixes
C0587Brake Booster Motor A Position Sensor Circuit/Open4 ranked fixes
C0588Brake Booster Motor A Position Sensor Circuit Low4 ranked fixes
C0589Brake Booster Motor A Position Sensor Circuit High4 ranked fixes
C058ABrake Booster Motor A Position Sensor Circuit Range/Performance4 ranked fixes
C058BBrake Booster Motor B Position Sensor Circuit/Open4 ranked fixes
C058CBrake Booster Motor B Position Sensor Circuit Low4 ranked fixes
C058DBrake Booster Motor B Position Sensor Circuit High4 ranked fixes
C058EBrake Booster Motor B Position Sensor Circuit Range/Performance4 ranked fixes
C0590Brake Booster Motor A Phase U-V-W Current High4 ranked fixes
C0591Brake Booster Motor A Phase U-V-W Current Low4 ranked fixes
C0592Brake Booster Motor B Phase U-V-W Current High4 ranked fixes
C0593Brake Booster Motor B Phase U-V-W Current Low4 ranked fixes
C0594Brake Booster Motor A Performance4 ranked fixes
C0595Brake Booster Internal Power Driver Range/Performance4 ranked fixes
C0596Brake Booster Motor A Current Sensor Circuit Range/Performance4 ranked fixes
C0599Brake Booster Control Module Missing Calibration4 ranked fixes
C05AFBrake Booster Motor B Current Sensor Circuit Range/Performance4 ranked fixes
C05B8Brake Booster Motor A Position Sensor Supply Circuit/Open4 ranked fixes
C05B9Brake Booster Motor A Position Sensor Supply Circuit Low4 ranked fixes
C05BABrake Booster Motor A Position Sensor Supply Circuit High4 ranked fixes
C05BBBrake Booster Motor A Position Sensor Supply Circuit Range/Performance4 ranked fixes
C05BCBrake Booster Motor B Position Sensor Supply Circuit/Open4 ranked fixes
C05BDBrake Booster Motor B Position Sensor Supply Circuit Low4 ranked fixes
C05BEBrake Booster Motor B Position Sensor Supply Circuit High4 ranked fixes
C05BFBrake Booster Motor B Position Sensor Supply Circuit Range/Performance4 ranked fixes
C05C2Brake Booster Motor A Over Temperature4 ranked fixes
C05C3Brake Booster Motor A Supply Circuit4 ranked fixes
C062CBrake Booster Motor 'B' Performance4 ranked fixes

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