CDL Air Brakes Test

2

This is the Commercial Vehicle Driver's License Test covering Air Brakes.  You will be presented with 40 questions and you must answer 34 questions correctly to pass.  There is no time limit.  You may not go back once you answer a question.  Click the "Start Quiz" button below to begin.  Good luck!

1 / 40

Should your air compressor stop working:

2 / 40

Select the purpose of fanning air brakes:

3 / 40

You should___to reduce the air leakage rate.

4 / 40

What does the drain valve for air tanks remove?

5 / 40

Front wheel brakes are good under what kind of conditions?

6 / 40

Select the statement that is not part of the air-brake system:

7 / 40

After the initial drop, the maximum leakage rates per minute is:

8 / 40

Is it mandatory that all vehicles with air brakes have low air pressure warning signals?

9 / 40

A leak rate for a straight truck or bus air brake system should not exceed _____psi per minute when the engine is off and the brakes are released.

10 / 40

Select how you would check the truck's slack adjusters.

11 / 40

The best way to test the low air pressure warning signal is to:

12 / 40

When should you drain air tanks that do not have an automatic tank drain?

13 / 40

What does the air compressor governor control?

14 / 40

What is a supply pressure gauge used for?

15 / 40

Spring brakes are usually held back by_____during normal driving.

16 / 40

____is what can legally hold the parking brake or emergency brake in position for a bus, truck, or truck tractor.

17 / 40

Select the inappropriate way to test for the low pressure warning signal.

18 / 40

Select the true statement in regards to your brake function when your ABS fails

19 / 40

Why are you required to take an exam about air brakes?

20 / 40

The safety valve is usually set to open at:

21 / 40

How often should you drain your air tanks?

22 / 40

Why do air brakes take longer to stop than hydraulic brakes?

23 / 40

At around____the governor allows the air compressor to start pumping again:

24 / 40

What are spring brakes?

25 / 40

Select the true statement in regards to brake drums or discs:

26 / 40

What does the service brake system do?

27 / 40

How do you determine if slack adjusters need to be adjusted?

28 / 40

When should you not use the parking brakes?

29 / 40

Select the first action to do when the low air pressure warning comes on:

30 / 40

What does it man when the safety valve releases air?

31 / 40

Commerical vehicles typically have this type of brake.

32 / 40

Water is drained from the compressed air tanks because:

33 / 40

Select when you should use the parking brake:

34 / 40

Air tanks should be drained:

35 / 40

Select how brakes work on long, steep downgrades:

36 / 40

A slack adjuster is:

37 / 40

You should be in the proper gear before going down a hill because:

38 / 40

You should_____when checking the slack adjusters on S-Cam brakes.

39 / 40

Air pressure loss in a vehicle with a fully charged air system should be less than_______after the initial drop and brake applied.

40 / 40

____is the most common type of foundation brakes used by heavy vehicles.

Your score is

The average score is 74%

5/5 - (1 vote)

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