C05CA

Brake Master Cylinder Piston Position Sensor A Circuit Voltage High

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

The brake system fault indicator is on
Reduced braking performance
ABS activation during normal braking
Unstable operation of the brake system

Causes

Master cylinder piston position sensor malfunction
Open or short circuit in wiring harness
Corrosion or poor contact in connectors
Malfunction of the brake control unit (ECU)

How to Fix

Check the integrity of the wiring harness and sensor connectors
Measure resistance and voltage at the sensor
Check sensor operation using a diagnostic scanner
Replace sensor or wiring harness if necessary
Test the system after repair

Related codes

C05CB C05CC C05CD