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 sensor that checks how much power the brake booster motor is using. It's like when a toy car's battery sensor isn't sure how much battery is left.
The code C05AF indicates an issue with the brake booster motor's current sensor, which is responsible for monitoring the electrical current used by the motor to ensure it operates within the correct range.
The C05AF code is triggered when the vehicle's control module detects that the current sensor for the brake booster motor B is not operating within its expected range or performance parameters. This could be due to electrical issues, sensor malfunction, or wiring problems.
• Brake warning light on the dashboard
• Reduced braking performance
• Unusual noises from the brake booster
• Faulty brake booster motor current sensor
• Damaged wiring or connectors
• Malfunctioning control module
Brake Booster: A device that increases the force applied to the brakes.
Current Sensor: A sensor that measures the flow of electrical current.
• Perform a visual inspection of the brake booster motor and wiring.
• Use a multimeter to check the continuity and resistance of the current sensor circuit.
• Scan the vehicle with an OBD-II scanner to confirm the code and check for other related codes.
• Replace the faulty brake booster motor current sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect brake system components.
• Ensure all electrical connections are secure.
• Perform routine maintenance checks.
Sensor Issue
• Do not ignore the brake warning light.
• Have the vehicle inspected by a professional as soon as possible.
Check with the vehicle manufacturer for specific warranty coverage on brake system components.
This code has been reported in vehicles with electronic brake systems where sensor performance is critical for safety.
High – Brake system issues should be addressed immediately to ensure vehicle safety.
Driving with impaired brakes is dangerous and may be illegal. Always ensure your vehicle's braking system is functioning properly.
• Vehicle parked on a level surface
• Engine off and keys removed
The brake booster motor and its current sensor are typically located near the firewall in the engine bay.
Q: Can I drive with the C05AF code?
A: It's not recommended to drive with this code active as it may affect braking performance.
Q: How do I reset the C05AF code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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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