ADT 7-4 Flashcards
Disc brakes use replaceable friction material called ________.
a. Linings
b. Pads
c. Core
d. Web
b. Pads
Drum brakes use replaceable friction material called ________.
a. Linings
b. Pads
c. Core
d. Web
a. Linings
Technician A says that a power-assisted brake reduces stopping distances compared with a non power-assisted brake system. Technician B says that the power-assisted brake system reduces the force that the driver must exert on the brake pedal. Which technician is correct?
Technician B only
A locked wheel ________ to the road surface than a rolling wheel.
a. Has less traction
b. Has greater traction
a. Has less traction
Technician A says that all vehicles equipped with ABS will experience pulsating brake pedal even during normal braking. Technician B says that some ABS units only control the rear wheel brakes. Which technician is correct?
Technician B only
The FMVSS 135 standards determine ________.
a. The design of the braking system
b. The performance of the braking system
c. The materials used in the braking system
d. All of the above
b. The performance of the braking system
An owner of a vehicle equipped with ABS brakes complained that whenever he tried to stop on icy or slippery roads, the brake pedal would pulse up and down rapidly. Technician A says that this is normal for many ABS units. Technician B says that the ABS unit is malfunctioning. Which technician is correct?
Technician A only
A brake snub is ________.
a. An event that results in an ABS stop
b. A brake event that causes the tires to slide on the pavement
c. A controlled brake application
d. A parking brake test procedure
c. A controlled brake application
All of the following are specified by FMVSS 135 except:
a. Brake burnish procedure
b. Variable brake proportioning system
c. Brake noise levels
d. Cold effectiveness
c. Brake noise levels
What is the purpose of any brake repair?
a. Reduce noise during braking
b. Replace pads and linings
c. Restore proper brake pedal height
d. Restore like-new performance
d. Restore like-new performance
All of the following are correct statements about braking EXCEPT:
a. Kinetic energy must be absorbed by the braking system
b. Kinetic energy of a vehicle doubles when the speed doubles
c. The heavier the vehicle, the greater the kinetic energy when moving
d. If the vehicle weight is doubled, the kinetic energy of a moving vehicle is doubled
b. Kinetic energy of a vehicle doubles when the speed doubles
Technician A says that the front brakes do most of the braking because the front brakes are larger. Technician B says that due to weight transfer, most of the braking force needs to be done by the front brakes. Which technician is correct?
Technician B only
The brake pedal assembly uses a mechanical lever to ________.
a. Increase the driver’s force on the pedal applied to the master cylinder.
b. Increase the distance the brake pedal needs to be depressed by the driver
c. Decrease the driver’s force on the brake pedal applied to the master cylinder
d. Allow for clearance between the brake pedal and the floor when the brakes are applied
a. Increase the driver’s force on the pedal applied to the master cylinder
The friction between two surfaces is affected by all EXCEPT:
a. Speed difference between the two surfaces
b. Surface finish
c. Frictional material
d. Heat
a. Speed difference between the two surfaces
Technician A says that the thicker or heavier the disc brake rotor, the more heat can be absorbed. Technician B says that the faster the vehicle is traveling when the brakes are applied, the greater the amount of heat created in the brake system. Which technician is correct?
Both Technicians A and B
All of the following are types of brake fade EXCEPT:
a. Mechanical fade
b. Lining fade
c. Gas fade
d. Rotor fade
d. Rotor fade
Brake fade caused by water can occur ________.
a. Only if the vehicle is driven in water above the centerline of the axle
b. Whenever it rains and the roads are wet or damp
c. Due to moisture in the air on a humid day
d. Whenever driving through water puddles or during a severe rainstorm
d. Whenever driving through water puddles or during a severe rainstorm
What can the driver do to reduce the possibility of brake fade caused by heat?
a. Ride the brakes to keep the shoes and pads against the rum or rotor
b. Pump the brake pedal while descending a steep hill
c. Select a lower transmission gear
d. Shift the transmission into neutral and allow the vehicle to coast down long or steep hills
c. Select a lower transmission gear
Maximum deceleration rates for a typical passenger car or light truck is ________.
a. 1 to 3 ft/sec
b. 5 to 10 ft/sec
c. 16 to 32 ft/sec
d. 200 to 250 ft/sec
c. 16 to 32 ft/sec
Disc brake pads can reach temperatures as high as ________.
a. 300 degrees F
b. 1000 degrees F
c. 1300 degrees F
d. 1800 degrees F
d. 1800 degrees F
Two technicians are discussing master cylinders. Technician A says that it is normal to see fluid movement in the reservoir when the brake pedal is depressed. Technician B says a defective master cylinder can cause the brake pedal to slowly sink to the floor when depressed. Which technician is correct?
Both Technicians A and B
If the brake pedal linkage is not adjusted correctly, brake fluid may not be able to expand back into the reservoir through the ________ of the master cylinder when the brakes get hot.
a. Vent port (forward hole)
b. Replenishing port (rearward hole)
a. Vent port (forward hole)
The primary brake circuit fails due to a leak in the lines, leaving the rear section of a dual split master cylinder. Technician A says that the driver will notice a lower than normal brake pedal and some reduced braking power. Technician B says that the brake pedal will “grab” higher than normal. Which technician is correct?
Technician A only
Two technicians are discussing a problem where the brake pedal travels too far before the vehicle starts to slow. Technician A says that the brakes may be out of adjustment. Technician B says that one circuit from the master cylinder may be leaking or defective. Which technician is correct?
Both Technicians A and B
Air in the lines will cause what type of problem?
a. Vibration in the brake pedal during stops
b. Low spongy brake pedal
c. Brake noise
d. Hard brake pedal
b. Low spongy brake pedal
The master cylinder is able to move about how much brake fluid during each brake operation?
a. One tablespoon
b. One teaspoon
c. One cu. in.
d. 50 ml
b. One teaspoon
Brake fluid pressure is measured in what unit?
a. Sq. in.
b. Pounds
c. Inches
d. PSI
d. PSI
How much brake fluid is in a typical master cylinder reservoir?
a. One gallon
b. Enough to allow all brakes to become completely worn
c. 15 to 20 liters
d. One pint
b. Enough to allow all brakes to become completely worn
What part in the master cylinder helps keep air from contacting the brake fluid yet allows the fluid level to drop as the disc brakes wear?
a. Vent valve
b. Compensating valve
c. Residual valve
d. Rubber diaphragm or floating disc
d. Rubber diaphragm or floating disc
The brakes on a vehicle work okay for a while, then the vehicle slows because the brakes self-applied. Technician A says that an overfilled master cylinder could be the cause. Technician B says that a blocked vent port (compensating port) could be the cause. Which technician is correct?
Both Technicians A and B
Technician A says a pull to the right during braking could be caused by a defective metering valve. Technician B says a pull to the left could be caused by a defective proportioning valve. Which technician is correct?
Neither Technicians A nor B
The rear brakes lock up during a regular brake application. Technician A says the metering valve could be the cause. Technician B says that stuck front disc brake calipers could be the cause. Which technician is correct?
Technician B only
The rear wheels lock up during hard braking. Technician A says that a defective metering valve could be the cause. Technician B says that a defective proportioning valve could be the cause. Which technician is correct?
Technician B only
A combination valve includes ________.
a. Metering and proportioning valves
b. Proportioning and pressure-differential valves
c. Proportioning, metering and pressure-differential valves
d. Any of the above depending on the make and model
d. Any of the above depending on the make and model
A residual check valve is used to ________.
a. Maintain a slight pressure on the hydraulic system
b. Prevent front wheel lockup during hard braking
c. Prevent rear wheel lockup during hard braking
d. Speed brake release to reduce brake wear
a. Maintain a slight pressure on the hydraulic system
Technician A says that the red brake warning light can be turned on if a difference in pressure is detected by the pressure-differential switch. Technician B says that the red brake warning light can be turned on if the brake fluid level sensor detected low brake fluid level. Which technician is correct?
Both Technicians A and B
Which type of vehicles most often do not use metering valves?
a. Rear-wheel drive
b. Four-wheel drive
c. Front-wheel drive
d. All-wheel drive
c. Front-wheel drive
A spongy brake pedal is being diagnosed. Technician A says that air in the hydraulic system could be the cause. Technician B says a defective pressure-differential switch could be the cause. Which technician is correct?
Technician A only
The button on the ________ valve should be held when pressure bleeding the brakes.
a. Metering
b. Proportioning
c. Pressure-differential
d. Residual check
a. Metering
A typical brake light is electrically ________.
a. Normally open
b. Normally closed
a. Normally open
The type of brake fluid most often recommended by vehicle manufacturers is ________.
a. DOT 3
b. DOT 4
c. DOT 5
d. DOT 5.1
a. DOT 3
Which of the following is NOT a characteristic of conventional brake fluid?
a. Absorbs moisture from the air
b. Removes paint if spilled on vehicle surfaces
c. Lasts the life of the vehicle unless there is a leak
d. Is clear or amber in color
c. Lasts the life of the vehicle unless there is a leak
Technician A says that DOT 5 brake fluid can be added to DOT 3 brake fluid. Technician B says that it is wise to purchase brake fluid that is in metal rather than plastic containers. Which technician is correct?
Technician B only
As brake fluid ages, what happens?
a. The boiling temperature decreases
b. The boiling temperature increases
c. The viscosity (thickness) decreases
d. The color changes to purple
a. The boiling temperature decreases
Technician A says that glycol-based brake fluid causes the seals to swell slightly. Technician B says that the DOT 5 (silicone based) brake fluid causes rubber seals to swell slightly. Which technician is correct?
Technician A only
The two types of flares used on brake lines are ________.
a. SAE and DOT
b. Double flare and ISO
c. Ball flare and bubble flare
d. SAE and double flare
b. Double flare and ISO
Two technicians are discussing why brake lines are coiled near the master cylinder on many vehicles. Technician A says that these coils help prevent moisture from flowing from the master cylinder to the calipers. Technician B says that they help prevent cracks that could be caused by vibrations. Which technician is correct?
Technician B only
Flexible brake hose should be inspected for all of the following EXCEPT:
a. Cracks
b. Leakage
c. Twisted
d. Worn outer ribs
d. Worn outer ribs
Why should brake calipers be supported by a wire during brake service and not allowed to hang by the flexible brake hose?
To help prevent damage to the brake hose
Used brake fluid should be ________.
a. Mixed with and recycled with used oil
b. Poured down the drain
c. Absorbed with a cloth or absorbent material and disposed of in regular trash
d. Poured onto open ground to reduce dust
c. Absorbed with a cloth or absorbent material and disposed of in regular trash
