Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is telling the dashboard to turn on the warning light for the brakes because it thinks there's a problem.
The Brake System Control Module B has detected an issue and is requesting the Malfunction Indicator Lamp (MIL) to be illuminated.
This code indicates that the Brake System Control Module B has identified a fault within the braking system that requires the MIL to be illuminated. This could be due to a malfunction in the module itself or an issue it has detected in the braking system.
• Brake warning light on the dashboard
• Possible reduced braking performance
• Unusual noises from the braking system
• Faulty Brake System Control Module B
• Wiring issues or poor connections
• Fault in the brake system detected by the module
MIL: Malfunction Indicator Lamp
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the Brake System Control Module B.
• Test the functionality of the Brake System Control Module B.
• Repair or replace faulty wiring or connections.
• Replace the Brake System Control Module B if necessary.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect brake system components.
• Ensure all connections are secure and free of corrosion.
• Perform routine brake system maintenance.
Brake System Issue
• Do not ignore the brake warning light; have it checked immediately.
• Avoid driving the vehicle until the issue is diagnosed and repaired.
Check with the vehicle manufacturer for warranty coverage on brake system components.
This code has been associated with issues in vehicles with electronic brake systems, particularly in models with advanced braking features.
High – Brake system issues can affect vehicle safety and should be addressed immediately.
Driving with a malfunctioning brake system can be dangerous and may violate vehicle safety regulations.
• Vehicle stationary with ignition on
• Perform tests in a safe environment
The Brake System Control Module B is typically located near the brake pedal assembly or within the engine compartment.
Q: Can I drive with the P25C9 code?
A: It's not recommended to drive with this code active, as it indicates a potential issue with the brake system.
Q: How do I reset the brake warning light?
A: After repairing the issue, use an OBD-II scanner to clear the code and reset the light.
Pro · Four-system diagnostics
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Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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