Your vehicle has hydraulic brakes. Why might the brake pedal go down too far when pressed?

• A. The vacuum exhauster isn't working
• B. The pedal travel requires adjustment
• C. There isn't enough fluid in the braking system
• D. There's too much fluid in the braking system

Answer: (C)

In a hydraulic braking system, pressing the pedal transfers your foot force into hydraulic pressure to apply the brakes. If the brake fluid level is too low, there isn’t enough fluid to be pressurized, so the system can’t develop the necessary braking pressure and the pedal sinks toward the floor. This low-fluid condition is a common reason for the pedal going down too far.

A vacuum assist problem would typically make the pedal feel harder to push (loss of assist), not cause it to drop fully to the floor. An adjustment issue might change how far the pedal travels, but it wouldn’t usually cause the pedal to go to the floor in a hydraulic system. Excess fluid isn’t the direct cause of the pedal sinking either.