ASE A5 Brakes Practice Test
51. A vehicle with a Hydroboost brake system has reduced braking performance. Which of these could be the cause?
- A. Low manifold vacuum.
- B. A faulty vacuum check valve.
- C. A clogged inlet valve.
- D. A faulty power steering pump.
Answer A is wrong. Hydroboost brake units use power steering pressure instead of engine vacuum for brake assist.
Answer B is wrong. The vacuum check valve controls the vacuum flow to a vacuum power booster.
Answer C is wrong. A clogged inlet valve blocks or slows the airflow into a vacuum booster.
Answer D is correct. The power steering pump produces pressure for the Hydroboost brake assist unit.
52. A vehicle with four-wheel disc brakes, ABS, and a vacuum brake booster has a hard brake pedal and an increased stopping distance. Which of the following is causing this condition?
- A. Bypassing master cylinder cup seals.
- B. A faulty brake booster.
- C. Worn brake pads.
- D. Air in the brake lines.
Answer A is wrong. Bypassing master cylinder internal seals causes a low brake pedal that fades to the floor.
Answer B is correct. Symptoms of a faulty or leaking brake booster include a hard brake pedal, increased pedal effort, and an extended stopping distance.
Answer C is wrong. Worn brake pads result in a squeal when braking.
Answer D is wrong. Air in the brake lines results in a soft spongy brake pedal.
53. A vehicle drifts to the right while driving forward. Which of these could be the cause?
- A. A seized left front caliper.
- B. A restriction in the left front brake line.
- C. Leaking master cylinder cup seals.
- D. Sticking right front caliper slide pins.
Answer A is wrong. A frozen left front caliper will cause the vehicle to pull to the right when braking.
Answer B is wrong. A restriction in the left front brake line will cause the left front brake to drag after the brakes are released.
Answer C is wrong. Leaking master cylinder cup seals result in an internal leak, causing pressure loss and the pedal to fade to the floor when braking.
Answer D is correct. The slide pins can stick in their bores, preventing sufficient braking force and causing the brake pad to drag and wear prematurely. As a result, while driving forward, the vehicle will drift or pull to the side with the dragging front brake.
54. The brake shoes on a self-energizing drum brake system require replacement. All of the following statements are correct about replacing these brake shoes EXCEPT:
- A. The primary shoe faces the front of the vehicle.
- B. The secondary shoe has a shorter brake shoe lining.
- C. The secondary shoe faces the rear of the vehicle.
- D. Shoe lining can be riveted or glued to the shoe.
Answer A is wrong. The primary shoe faces the front of the vehicle.
Answer B is correct. The shoe with the shorter lining (the primary shoe) faces the front of the vehicle. Reversing the primary and secondary brake shoes results in noise, possible wheel lockup, and a pull to one side while driving forward.
Answer C is wrong. The secondary shoe faces the rear of the vehicle.
Answer D is wrong. Shoe lining can be riveted or glued to the shoe. Click or tap the Read more... button for an illustrated explanation.
55. The front brake pads on a vehicle with a quick take-up master cylinder need replacement. They were recently replaced. Technician A says this is a low-drag brake system. Technician B says the master cylinder's quick take-up valve could be sticking. Who is correct?
- A. Technician A
- B. Technician B
- C. Both A and B
- D. Neither A or B
Answer A is wrong. Both technicians are correct. This type of master cylinder is used with low-drag brake calipers. It is distinguishable by a large diameter piston and primary low-pressure bore located at the back or push rod end of the master cylinder.
Answer B is wrong. The quick take-up master cylinder provides more brake fluid volume to add space between the pads and the rotor. They are fuel-efficient.
Answer C is correct. Both technicians are correct.
Answer D is wrong. Both technicians are correct.