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 reading the pressure in the brakes. It's like the car can't tell how hard you're pressing the brake pedal.
The C0647 code is triggered when the brake pressure sensor circuit shows a low voltage condition, indicating a possible issue with the sensor or its wiring.
The brake pressure sensor measures the pressure applied to the brake system and sends this information to the vehicle's control module. A 'Circuit Low' condition indicates that the sensor is sending a voltage signal that is lower than the expected range, which could be due to a malfunctioning sensor, wiring issues, or a problem with the control module.
• ABS warning light on
• Reduced braking performance
• Brake pedal feels different
• Faulty brake pressure sensor
• Damaged or corroded wiring/connectors
• Faulty control module
ABS: Anti-lock Braking System
OBD-II: On-Board Diagnostics, second generation
• Inspect the brake pressure sensor and wiring for damage.
• Use a multimeter to check the voltage at the sensor.
• Check the control module for faults.
• Replace the faulty brake pressure sensor.
• Repair or replace damaged wiring/connectors.
• Reprogram or replace the control module if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Buick Enclave
• Regularly inspect brake system components.
• Ensure connectors are free from corrosion.
• Follow recommended maintenance schedules.
Sensor Issue
• Do not ignore the ABS warning light.
• Have your brakes inspected by a professional.
• Avoid hard braking until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on brake system components.
This code has been reported in vehicles with known brake system issues, often related to sensor or wiring faults.
High – Brake system issues can affect vehicle safety.
Driving with a malfunctioning brake system can be dangerous. Address this issue promptly to ensure vehicle safety.
• Vehicle ignition on
• Brake pedal pressed
The brake pressure sensor is typically located near the master cylinder or integrated into the ABS module.
Q: Can I drive with a C0647 code?
A: It's not recommended to drive with this code active, as it can affect your braking performance.
Q: How do I reset the ABS light?
A: After repairs, use an OBD-II scanner to clear the code and reset the ABS light.
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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