ASE A5 Brakes Practice Test

26. A ridge has formed on the backing plate's pads where the brake shoes rest. All of the following are correct EXCEPT:

  • A. Apply bearing grease to reduce brake squeak.
  • B. They may be filed to restore a smooth finish.
  • C. They may be sanded to restore a smooth finish.
  • D. Apply a lubricant for high-temperature brake systems.

26.

Answer A is correct. Avoid petroleum-based greases that can swell rubber parts and chassis greases that burn off and evaporate.

Answer B is wrong. The shoe pads on the backing plate can become scuffed and grooved as the shoes move back and forth on its surface. These pads can be sanded or filed smoothly to restore surface integrity.

Answer C is wrong. Steel plate backing plates hold and assemble wheel cylinders, brake shoes, and other hardware onto a drum brake unit.

Answer D is wrong. Always use the proper high-temperature lubricant between the backing plate and the shoe.

27. The master cylinder is full of clean brake fluid, the brake pads and shoes are in good condition, and there are no brake warning lights. However, the brake pedal is low and feels soft. Which of the following could be the cause?

  • A. Over-adjusted rear brake shoes.
  • B. Worn front brake pads.
  • C. Air bubbles in the brake fluid.
  • D. A leaking vacuum brake booster.

27.

Answer A is wrong. Over-adjusted rear brake shoes result in overheating, brake drag, and possible wheel lockup.

Answer B is wrong. Worn brake pads result in noise from the chatter clips or a warning lamp from the electronic brake pad wear indicator.

Answer C is correct. Air is compressible and results in a low spongy feeling brake pedal. In addition, today's hybrid and electric vehicles use brake stroke simulators that can fail, affecting the brake pedal's feel.

Answer D is wrong. A leaking vacuum booster results in a hard brake pedal, increased pedal effort, and an extended stopping distance.

28. A vehicle with a four-wheel disc ABS brake system is difficult to bleed and still has a low spongy brake pedal. Technician A says the master cylinder may have faulty cup seals. Technician B says to bleed the ABS hydraulic modulator valve assembly. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

28.

Answer A is wrong. Isolate the master cylinder by blocking the outlet ports with plugs and checking the pedal for firmness. If the pedal is firm, the master cylinder cup seals are good, and the problem exists downstream of the master cylinder.

Answer B is wrong. Air can get trapped in the ABS unit, a line or hose, or one of the brake units.

Answer C is correct. Air is compressible, resulting in a spongy brake pedal.

Answer D is wrong. Both Technicians are correct.

29. A height sensing proportioning valve:

  • A. Delays pressure to the front brakes.
  • B. Prevents rear wheel lockup.
  • C. Prevents nosedive while braking.
  • D. Is adjusted with all four tires raised in the air.

29.

Answer A is wrong. The metering valve holds off pressure to the front brakes until the rear drum brakes overcome spring pressure.

Answer B is correct. Proportioning valves enable balanced braking by reducing hydraulic pressure to the rear brake units during sudden and panicked braking. This reduction in pressure helps prevent rear-wheel lockup.

Answer C is wrong. The metering valve prevents nosedive.

Answer D is wrong. Adjust a height-sensing proportioning valve at curb height with all four tires firm on the ground. Adjusting this proportioning valve on a lift would reduce rear brake performance.

30. A scan of a light truck with four-wheel ABS indicates a fault code for the left rear wheel speed sensor. Technician A says this could be caused by mud and road debris caught between the tone sprocket and the sensor. Technician B says to check the wheel bearing for looseness and wear. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

30.

Answer A is wrong. Mud and road debris can get in the gap or between the tone sprockets, creating a problem with the signal.

Answer B is wrong. The tone rings for these speed sensors spin with the hub or CV axle; loose wheel bearings cause the sensor's ring to wobble.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Inspect the wheel bearings by grasping the tire at the top and bottom and rocking it back and forth. Excessive play indicates a loose wheel bearing.