Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CDL > CDL AIR Brake Test > Flashcards

CDL AIR Brake Test Flashcards

1
Q

During normal driving, spring brakes are usually held back by?

A. Bolts
B. Air pressure
C. Spring pressure

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The brake pedal in an air brake system

A. Controls the speed of the air compressor
B. Controls the air pressure applied to put on the brakes
C. Is connected to slack adjusters by a series of rods and linkages

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The brake system that applies and releases the brakes when the driver uses the brake pedal is what system?

A. Emergency system
B. Service system
C. Parking system

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

All air brake equipped vehicles must have what?

A. A supply pressure gauge
B. An application gauge
C. A backup hydraulic system

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If your truck or bus has a dual parking control valve, you can use pressure from another tank to

A. Release the spring brakes to move the vehicle in an emergency
B. Apply more pressure if the main tank is getting low
C. Balance the service brake system whenever you are parked

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The most common type of foundation brake found on heavy vehicles is the

A. Wedge brake
B. S-cam drum brake
C. Disc brake

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Parking or emergency brakes of trucks and buses can be legally held on by what

A. Spring pressure
B. Fluid pressure
C. Air pressure

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

If your vehicle has an alcohol evaporator, it is there to

A. Rid the wet tank of alcohol that collects and sits at the bottom
B. Eliminate the need for daily tank draining
C. Reduce the risk of ice in valves and other parts in cold weather

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Some air brake systems have an alcohol evaporator. What might happen of you don’t keep the unit filled with alcohol?

A. The s-cam may not rotate back when you release the pedal
B. Ice may form in the tanks and cause the brakes to fail
C. Ice may form on the drums and warn them

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The most important thing to do when the low air pressure warning comes on is

A. Downshift
B. Turn the warning off
C. Stop and park safely as soon as possible

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The driver must be able to see a low air pressure warning that must come on before pressure in the tanks fall below what?

A. 40psi
B. 60psi
C. 80psi

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Under normal conditions, in order to engage the parking brake the driver must first

A. Turn off the engine
B. Let the air out of the system
C. Be sure that the system is fully pressurized

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

To check the free play of Manuel slack adjusters on s-cam brakes, you should park on

A. Level ground, chock the wheels, and release the parking brakes
B. Level ground with the parking brake, then apply the service brake
C. Level ground and drain off air pressure before adjusting brakes

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If your vehicle has an alcohol evaporator, every day during cold weather you should

A. Check and fill the alcohol level
B. Change the alcohol from a new bottle
C. Check the oil for alcohol content

A

Check and fill the alcohol level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

For air brake systems in good condition the air compressor should start pumping at what psi? ‘

A. 100
B. 125
C.150

A

100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A straight truck or bus system should not leak at a rate of more then - psi per minute with the engine off and the brakes released?

A. 1
B. 2
C. 3

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A slack adjust or probably needs adjustment if it moves more than— inch when you pull on it

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The use of brakes on a long or steep downgrade is only a supplement to

A. The use of the spring brakes
B. The use of the front brake limiting valve
C. The braking effect of the engine

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Under ideal conditions, a truck with air brakes going 55 mph would require a stopping distance of what?

A. Less than 100 feet
B. 100-300 feet
C. More than 300 feet

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Emergency stab braking is when you

A. Press hard on the brake pedal and use the hand valve until the stop
B. Use light steady pressure on the pedal
C. Brake as hard as you can, release the brakes when the wheels lock, and apply the brakes again when the wheels roll

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The braking power of the spring brakes

A. Is not affected by the condition of the service brakes
B. Depends on the brakes being in adjustment
C. Increases when the service brakes get hot

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

If you must make an emergency stop you should brake so you

A. Can use the hand brakes before the pedal
B. Can keep your vehicle in a straight line and turn if it becomes necessary
C. Can use the full power of the brakes to lock them

A

B

23
Q

The proper method of braking when going down hills is to reduce your speed by mph below your safe speed before releasing the brakes?

A. 5
B. 10
C. 15

A

A

24
Q

Which of the following about ABS is true?

A.ABS changes the way you brake in an emergency
B. ABS allows you to follow more closely, drive faster, and less carefully
C. ABS will not help you avoid skids from over braking

A

A

25
Q

If your ABS is not working, you should

A. Not drive until the system is repaired
B. Drive normally, but get the system serviced soon
C. Drive at a lower speed and get the system repaired when ever you want

A

B

26
Q

The stop light switch

A. Turns on the brake lights to warn others behind you
B. Tells you when you need to use the emergency brakes
C. Tells you when the air system is low on air

A

A

27
Q

If air pressure does not build up to normal within the correct amount of time

A. You should be ready to use the parking brake to stop
B. The alcohol container may be low
C. Your air pressure may drop to low while driving requiring an emergency stop

A

C

28
Q

If the spring brakes are on, when should you push the brake pedal

A. Only when driving down a hill
B. Only on a slippery road
C. Never

A

C

29
Q

If your trucks compressor has its own oil supply, when should you first check the oil level?

A. Before driving
B. During your first en route inspection
C. Immediately after stopping

A

A

30
Q

The safety valve is set automatically to reduce pressure in the tanks at what psi

A. 50
B. 100
C. 150

A

C

31
Q

The air loss rate for a straight truck or bus with the engine off and the brakes on should not be more than what?

A. 1psi in 1 minute
B. 2psi in 45 seconds
C. 3psi in 1 minute

A

C

32
Q

Air brakes take more time to stop that hydraulic brakes because

A. Air brakes use a different drum
B. Air takes more time to flow through the lines than hydraulic fluid
C. Air brakes require a heavier return spring

A

B

33
Q

In air braked vehicles, the parking brake should be used

A. As little as possible
B. Any time the vehicle is parked
C. To hold your speed going down hills

A

B

34
Q

Which of these is not the proper time to apply the parking brakes

A. If the brakes are very hot
B. If you will only be stopped for less than 15 minutes
C. If you are going to test the parking brake to make sure that it holds

A

A

35
Q

Emergency controlled braking is when you

A. Apply the brakes as hard as you can without locking the wheels
B. Brake as hard as you can, and release the brakes when the wheels lock
C apply the hand valve as hard as you can, then push the pedal

A

A

36
Q

The application pressure gauge shows you how much pressure

A. You have in the air tanks
B. You are applying to the brakes
C. You have the modulation control valve

A

B

37
Q

The supply pressure gauge show how much pressure

A. Is in the air tanks
B. You have used on the trip
C. Is going to the brake chamber

A

A

38
Q

How often should you drain water and oil from your air tanks

A. Every 4 hours
B. At the end of each day of driving
C. Once a week

A

B

39
Q

The spring brakes on trucks will bring it to a stop automatically when air pressure falls to what range

A. 20-45psi
B. 60-80psi
C. 100-125psi

A

A

40
Q

The air compressor should stop pumping at what psi?

A. 100
B. 125
C. 150

A

B

41
Q

Modern air brakes combine 3 different systems. The service, parking and ——- brakes

A

A

42
Q

The s-cam

A. Controls the flow of air into each brake chamber
B. Pulls the brake shoes away
C. Drums and allows the wheels to roll freely forces the brake shoes to the drums

A

C

43
Q

If your truck has a dual air system and 1 system is low on air pressure

A. The drums will not be fully pressurized
B. Either the front or rear brakes will not be operating fully
C. The manual slack adjusters are not set properly

A

B

44
Q

Excessive use of the service brakes results in overheating, which can lead to

A. Improper adjustment of the s-cam
B. Increased contact between the drum and shoes
C. Expansion of the brake drum

A

C

45
Q

If your truck has a properly functioning dual air system, the pressure should build from 85 psi to 100 psi in how long

A. 30 seconds
B. 45 seconds
C. 60 seconds

A

B

46
Q

You should know that your brakes are fading when

A. You have to push harder and harder on the brake pedal to control your speed
B. The brake pedal feels spongy when pressure is applied
C. Pressure on the pedal is released and you slow down

A

A

47
Q

How should you check that your service brakes are working properly

A. Park on a slight incline,drain off pressure and check for movement
B. Park on level ground, release the parking brakes, roll forward slowly and apply the brakes using the pedal

A

B

48
Q

Total stopping distance for air brakes is longer than hydraulics because of what

A. Brake lag
B. Reaction
C. Effective braking

A

A

49
Q

Excessive heat caused by using your brakes too often can cause the

A. Modulating control valve to wear out
B. Brake lines to plug
C. Brakes to fade or fail

A

C

50
Q

If a truck or bus has ABS, it will have a ——- malfunction lamp on the instrument panel

A. Red
B. Yellow
C. Green

A

B

51
Q

The modulating control valve allow you to operate the

A. Spring brakes
B. Front brakes
C. Amount of air pressure in the system

A

A

52
Q

Cracks in the drum can not be longer than the width of the friction area

A. 2
B. 1/2
C. 1/3

A

B

53
Q

The air brake lag at 55mph adds how many feet of stopping distance

A. 12 feet
B. 32 feet
C. 60 feet

A

B

CDL (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions