ASE Brakes Certification Practice Exam 2025 – Complete Study Resource

When a vacuum power booster is functioning properly during a leak test, you should expect the brake pedal to hold steady. This indicates that the booster is maintaining proper vacuum pressure and there are no leaks in the system. In a functioning vacuum booster, when the brake pedal is pressed, the booster aids in amplifying the force applied to the pedal, which helps in providing adequate braking power.

If the system is sealed and operating correctly, the pedal should not move significantly after being depressed; it should remain in its position. This steady hold signifies that the vacuum booster is effectively assisting in the braking process and that there is a sufficient vacuum present to provide that assistance. A rapid pulsation or sinking of the pedal would suggest issues such as an internal leak or a failure within the booster, while a slow rise would imply that the brake fluid is potentially low or that there is a problem with the hydraulic system.