Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is detecting a problem with the sensor that tells it where the brake pedal is. It's saying the sensor is sending a signal that's too high.
The brake master cylinder piston position sensor monitors the position of the brake pedal. If the voltage from this sensor is higher than expected, the code C05CA is triggered.
The C05CA code is set when the Brake Master Cylinder Piston Position Sensor A outputs a voltage that exceeds the maximum threshold set by the manufacturer. This sensor is crucial for the vehicle's braking system as it helps in determining the position of the brake pedal, which is used by various systems like ABS and stability control.
• ABS warning light illuminated
• Unresponsive or overly sensitive braking
• Inconsistent brake pedal feel
• Possible loss of some braking functions
• Faulty brake master cylinder piston position sensor
• Wiring issues such as short circuits or open circuits
• Faulty or damaged connector
• Faulty brake control module
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
ABS: Anti-lock Braking System, a safety system that prevents the wheels from locking up during braking.
• Use an OBD-II scanner to confirm the code
• Inspect the brake master cylinder piston position sensor and its wiring
• Check the connector for corrosion or damage
• Test the sensor output voltage with a multimeter
• Replace the brake master cylinder piston position sensor if faulty
• Repair or replace damaged wiring or connectors
• Reset the vehicle's computer system
• Test drive the vehicle to ensure proper operation
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular inspection of brake system components
• Ensure proper maintenance of electrical connections
• Avoid exposure to excessive moisture and contaminants
Sensor Issue
• Do not ignore the ABS warning light
• Have the vehicle inspected by a professional if unsure
• Regularly check brake system components during maintenance
Warranty coverage may vary; check with the manufacturer or dealer for specific details.
This code has been associated with issues in vehicles with advanced braking systems, particularly in models with electronic brake control modules.
High – Brake system issues can affect vehicle safety and should be addressed promptly.
Driving with a malfunctioning brake system can be dangerous and may violate vehicle safety regulations.
• Vehicle stationary with ignition on
• Brake pedal pressed and released
The brake master cylinder piston position sensor is typically located near the brake pedal or integrated into the brake master cylinder.
Q: Can I drive with this code?
A: It's not recommended to drive with this code active as it may affect the braking system's performance.
Q: Will this code clear itself?
A: The code may clear itself if the issue is resolved, but it's best to manually clear it with an OBD-II scanner after repairs.
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Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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