Pennsylvania CDL Practice Exam

To check hydraulic brakes effectively, pumping the brake pedal three times and then holding it is the correct method. This process helps assess the brake system's responsiveness and fluid level. By pumping the pedal, you build up hydraulic pressure, which allows you to determine if the pedal feels firm or sinks gradually. If the pedal does sink while holding it, it can indicate a potential issue such as air in the brake lines, a leak in the hydraulic system, or worn brake components.

Holding the pedal after pumping gives you a clear indication of how well the brakes are functioning. If the pedal stays firm, it suggests that the hydraulic system is intact and pressurized as it should be. Conversely, if it loses pressure when held, it signifies a problem that needs attention.

Other methods mentioned, such as pressing the pedal continuously for five seconds, may not give as clear a picture of the brake system's condition. Likewise, checking only when the vehicle is stationary is limited, as a comprehensive test should encompass evaluating the brakes under operating conditions, which involves the multi-pump method.