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 having trouble talking to a sensor that helps it know how hard you're pressing the brakes.
The C0645 code indicates an issue with the brake pressure sensor circuit, specifically that it is open or not functioning correctly.
The brake pressure sensor is responsible for measuring the pressure applied to the brake system. An open circuit or fault in the sensor's wiring can prevent the sensor from sending accurate data to the vehicle's control module, affecting braking performance.
• ABS warning light on
• Brake system warning light on
• Reduced braking performance
• Faulty brake pressure sensor
• Damaged or corroded wiring/connectors
• Faulty control module
OBD-II: On-Board Diagnostics, a standardized system for vehicle diagnostics.
ABS: Anti-lock Braking System, a safety system that prevents wheels from locking up during braking.
• Use an OBD-II scanner to confirm the code.
• Inspect the brake pressure sensor and its wiring for damage.
• Check the connectors for corrosion or loose connections.
• Replace the brake pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reset the vehicle's control module to clear the code.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect brake system components.
• Keep electrical connections clean and secure.
• Follow scheduled maintenance for brake systems.
Sensor Issue
• Do not ignore brake warning lights.
• Seek professional help if unsure about repairs.
Check with the vehicle manufacturer for specific warranty coverage on brake components.
This code has been associated with vehicles using advanced brake systems with electronic control modules.
High – Brake system issues should be addressed immediately to ensure safety.
Driving with a malfunctioning brake system can be dangerous and may violate vehicle safety regulations.
• Vehicle parked on a level surface
• Engine off and cool
The brake pressure sensor is typically located near the brake master cylinder or within the ABS module.
Q: Can I drive with a C0645 code?
A: It's not recommended to drive with this code active, as it can affect braking performance and safety.
Q: How can I clear the C0645 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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