Question 1

A metering valve is found only on cars and trucks with ______.
A)four wheel disc brakes
B)four wheel drum brakes
C)disc front and drum rear brakes
D)dual diagonal brake circuits

Accepted Answer

Metering valves are typically found on vehicles with disc front and drum rear brakes to balance the braking pressure between the front and rear.

Question 2

A master cylinder that has a bulge at the rear, near the mounting flange, is a _____type master cylinder.
A)self-compensating
B)auto compensating
C)dual stage
D)quick take-up

Accepted Answer

A master cylinder with a bulge at the rear, near the mounting flange, is known as a quick take-up type. This design feature is typically used to quickly fill the brake lines and ensure prompt brake pad engagement with the rotor, especially in systems with low drag caliper designs.

Question 3

Technician A says power brakes are designed with vacuum-assisted units that use engine vacuum. Technician B says power brakes are designed with vacuum-assisted units that use vacuum developed by an external pump. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Power brakes can be designed with vacuum-assisted units that use either engine vacuum or vacuum developed by an external pump, making both Technician A and Technician B correct.

Question 4

Brake lines are made of ______.
A)seamless copper tubing
B)extruded copper clad aluminum tubing
C)double-wall steel tubing
D)All the answers are correct.

Accepted Answer

Brake lines are typically made of double-wall steel tubing due to its strength and resistance to corrosion, which is essential for the safety and reliability of brake systems.

Question 5

The brake light (stop light)switch is located _____ on modern vehicles.
A)on the master cylinder
B)on a bracket above the brake pedal
C)on the combination valve
D)All the answers are correct.

Accepted Answer

The brake light (stop light) switch is typically located on a bracket above the brake pedal in modern vehicles. This position allows the switch to activate the brake lights when the brake pedal is pressed.

Question 6

An aluminum master cylinder ______.
A)has a plastic fluid reservoir
B)has an anodized bore
C)is often called a composite master cylinder
D)all answers are correct

Accepted Answer

Aluminum master cylinders can have plastic fluid reservoirs, anodized bores to prevent corrosion, and are often referred to as composite master cylinders due to their construction materials.

Question 7

If the master cylinder has a large rear chamber and a smaller front chamber, _____.
A)the large chamber supplies fluid for the rear drum brake
B)the large chamber supplies fluid for the front disc brakes
C)the vehicle has a dual diagonal split brake system
D)the vehicle has four wheel disc brakes

Accepted Answer

The large chamber in the master cylinder typically supplies fluid for the front disc brakes because disc brakes require more fluid volume and pressure due to their design and the higher braking forces they handle compared to drum brakes.

Question 8

A technician is diagnosing a vehicle with a braking system problem. When she removes the filler cap to check the fluid level in the master cylinder, she notices that the rubber seal on the cap is swollen and has begun to disintegrate. What could be the problem?
A)water in the brake fluid
B)petroleum-based lubricants in the fluid
C)fluid overheating
D)incorrect type of brake fluid

Accepted Answer

Petroleum-based lubricants can cause rubber components in the braking system to swell and disintegrate.

Question 9

Organic friction material _____ semimetallic materials.
A)is quieter than
B)is more fade resistant than
C)requires higher pedal pressure than
D)wears out faster than

Accepted Answer

Organic friction material is quieter than semimetallic materials because it contains less metal, which reduces noise.

Question 10

A technician is diagnosing a car that had both front brake hoses replaced 5,000 miles ago. An inspection reveals that the right front brake hose has ruptured. Technician A says the specifications called for DOT 3 fluid; using DOT 4 fluid caused the failure. Technician B says the brake hose was twisted and stressed too much when installed. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Technician B is correct because a twisted or improperly installed brake hose can lead to stress and eventual rupture. The type of brake fluid (DOT 3 vs. DOT 4) would not cause a brake hose to rupture, as both types are compatible and DOT 4 can often be used in systems designed for DOT 3 without causing damage to the hoses.

Question 11

Synthetic linings are made of _____
A)fiberglass
B)aramid fiber
C)both A and B
D)neither A nor B

Accepted Answer

Synthetic linings can be made from various types of synthetic fibers, including fiberglass and aramid fiber. Both of these materials are used in different applications for their strength, durability, and resistance to heat and chemicals.

Question 12

Technician A says when the Brake warning light is illuminated, there is a difference in pressure between the two brake hydraulic circuits. Technician B says the Brake warning light is illuminated when the fluid level in the master cylinder reservoir is low. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Both Technician A and Technician B are correct. The Brake warning light can be illuminated for several reasons, including a difference in pressure between the two brake hydraulic circuits, which could indicate a leak or failure in one part of the system, and a low fluid level in the master cylinder reservoir, which could indicate a leak or that brake pads are worn and need replacement.

Question 13

Technician A says the size of the pads, shoes, drums, and rotors is based on the weight of the vehicle. Technician B says their size is based on the top speed the vehicle can achieve. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

The answer of Technician A says the size of the...

Question 14

Factors that determine a vehicle's braking power are being discussed. Technician A says the coefficient of friction between the pad and rotor or shoe and drum is a factor. Technician B says heat dissipation from brake components is a factor. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Both the coefficient of friction between the pad and rotor or shoe and drum and heat dissipation from brake components are crucial factors in determining a vehicle's braking power. The coefficient of friction affects how effectively the brake pads or shoes can slow the wheel, while heat dissipation is important because brakes can become less effective if they overheat.

Question 15

Which of the following is NOT used as a friction material in NAO brake pads?
A)nut shells
B)asbestos
C)powdered metals
D)graphite

Accepted Answer

Asbestos is not used in NAO (Non-Asbestos Organic) brake pads, as the term "non-asbestos" implies the exclusion of asbestos, which was traditionally used in brake pads but has been phased out due to health concerns.

Question 16

Semimetallic brake linings are being discussed. Technician A says they are more efficient than organic linings at low temperatures. Technician B says they are more fade resistant than organic materials but require higher brake pedal effort. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Semimetallic brake linings are generally more fade resistant than organic materials, but they often require higher brake pedal effort. They are not necessarily more efficient than organic linings at low temperatures.

Question 17

If a force of 150 pounds is applied to a master cylinder with a piston area of 1 square inch, how much force is developed on a wheel cylinder that has a piston area of 2 square inches?
A)75 pounds
B)150 pounds
C)300 pounds
D)450 pounds

Accepted Answer

The principle at work here is Pascal's Law, which states that pressure in a confined fluid is transmitted undiminished in every direction and acts with equal force on equal areas. The pressure applied by the master cylinder can be calculated as force divided by area, which is 150 pounds / 1 square inch = 150 PSI. This pressure is then applied to the wheel cylinder, which has an area of 2 square inches. The force developed on the wheel cylinder is therefore pressure times area, or 150 PSI * 2 square inches = 300 pounds.

Question 18

As brake fluid absorbs moisture, _____.
A)it becomes acidic
B)it becomes alkaline
C)it oxidizes
D)its boiling point drops

Accepted Answer

As brake fluid absorbs moisture, its boiling point drops, which can compromise braking performance by causing brake fade under high temperature conditions, such as during prolonged braking or in heavy traffic.

Question 19

Technician A says low-drag calipers retract the pistons and pads farther from the rotor than traditional calipers. Technician B says systems that use low-drag calipers cannot use quick take-up master cylinders. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Technician A is correct because low-drag calipers are designed to retract the pistons and pads farther from the rotor to reduce drag and improve fuel efficiency. Technician B is incorrect because systems with low-drag calipers can indeed use quick take-up master cylinders, which are designed to quickly move the pads into contact with the rotor to compensate for the increased retraction distance.

Question 20

A proportioning valve reduces fluid pressure to ______.
A)the front brakes during initial brake (low pedal force)application
B)the rear brakes during initial (low pedal force)brake application
C)the front brakes during hard braking
D)the rear brakes during hard braking

Accepted Answer

A proportioning valve is designed to reduce the fluid pressure to the rear brakes during hard braking to prevent the rear wheels from locking up, ensuring better control and stability of the vehicle.

Quiz 50: Brake Systems

A metering valve is found only on cars and trucks with ______.

A master cylinder that has a bulge at the rear, near the mounting flange, is a _____type master cylinder.

Technician A says power brakes are designed with vacuum-assisted units that use engine vacuum. Technician B says power brakes are designed with vacuum-assisted units that use vacuum developed by an external pump. Who is correct?

Brake lines are made of ______.

The brake light (stop light) switch is located _____ on modern vehicles.

An aluminum master cylinder ______.

If the master cylinder has a large rear chamber and a smaller front chamber, _____.

A technician is diagnosing a vehicle with a braking system problem. When she removes the filler cap to check the fluid level in the master cylinder, she notices that the rubber seal on the cap is swollen and has begun to disintegrate. What could be the problem?

Organic friction material _____ semimetallic materials.

Synthetic linings are made of _____

Technician A says when the Brake warning light is illuminated, there is a difference in pressure between the two brake hydraulic circuits. Technician B says the Brake warning light is illuminated when the fluid level in the master cylinder reservoir is low. Who is correct?

Technician A says the size of the pads, shoes, drums, and rotors is based on the weight of the vehicle. Technician B says their size is based on the top speed the vehicle can achieve. Who is correct?

Factors that determine a vehicle's braking power are being discussed. Technician A says the coefficient of friction between the pad and rotor or shoe and drum is a factor. Technician B says heat dissipation from brake components is a factor. Who is correct?

Which of the following is NOT used as a friction material in NAO brake pads?

Semimetallic brake linings are being discussed. Technician A says they are more efficient than organic linings at low temperatures. Technician B says they are more fade resistant than organic materials but require higher brake pedal effort. Who is correct?

If a force of 150 pounds is applied to a master cylinder with a piston area of 1 square inch, how much force is developed on a wheel cylinder that has a piston area of 2 square inches?

As brake fluid absorbs moisture, _____.

Technician A says low-drag calipers retract the pistons and pads farther from the rotor than traditional calipers. Technician B says systems that use low-drag calipers cannot use quick take-up master cylinders. Who is correct?

A proportioning valve reduces fluid pressure to ______.