Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that helps you press the brakes more easily. It's like when a helper isn't doing their job well.
The C0594 code indicates a performance issue with the brake booster motor, which assists in applying the brakes.
The brake booster motor is responsible for providing additional force to the brake pedal, making it easier for the driver to apply the brakes. A performance issue could mean the motor is not generating enough force or is malfunctioning.
• Increased effort required to press the brake pedal
• Reduced braking performance
• Brake warning light illuminated
• Faulty brake booster motor
• Electrical connection issues
• Malfunctioning brake booster sensor
Brake Booster: A device that increases the force applied to the brake pedal.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnosing vehicle issues.
• Check for any stored codes and clear them.
• Inspect the brake booster motor and related wiring for damage.
• Test the brake booster motor for proper operation.
• Replace the brake booster motor if faulty.
• Repair or replace damaged wiring or connectors.
• Reset the vehicle's computer system to clear the code.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance of the brake system
• Periodic inspection of electrical connections
• Prompt attention to brake warning lights
Brake System Performance
• Do not ignore the brake warning light.
• Have the brake system inspected by a professional.
• Avoid driving the vehicle until the issue is resolved.
Check with your vehicle manufacturer for specific warranty coverage on brake components.
The C0594 code has been reported in vehicles with electronic brake systems, particularly in models with advanced braking technology.
High – Brake performance issues can lead to unsafe driving conditions and should be addressed immediately.
Driving with compromised brake performance can be dangerous and may violate vehicle safety regulations.
• Vehicle parked on a level surface
• Engine running and brake pedal pressed
The brake booster motor is typically located near the firewall in the engine compartment, connected to the brake master cylinder.
Q: Can I drive with a C0594 code?
A: It's not recommended to drive with this code, as it indicates a problem with your brakes.
Q: How can I reset the C0594 code?
A: After repairs, use an OBD-II scanner to clear the code from the vehicle's computer.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
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Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
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