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CDL - Complete Practice Test Study Package Practice Tests

Free CDL - Section 5 - Air Brakes Sample Practice Test

You are about to take the CDL - Section 5 - Air Brakes. This sample test consists of 10 multiple choice questions and answers.

Please select the best answer for each question below and then click "Grade It!"

1. What does the air compressor do?
a.
The air compressor pumps air into the storage tanks (reservoirs).
b.
The air compressor is used to hold compressed air.
c.
The air compressor puts alcohol into the air system.
2. What does the air compressor governor do?
a.
The governor controls when the air compressor will pump air into the air storage tanks.
b.
The governor is used to hold compressed air.
c.
The governor pumps air into the air storage tanks.
d.
None of the above
3. When air tank pressure rises to the "cut-out" level, the governor stops the compressor from pumping air. What level is the "cut-out" level?
a.
Around 125 pounds per square inch or "psi"
b.
Around 100 pounds per square inch or "psi"
c.
Around 150 pounds per square inch or "psi"
d.
None of the above
4. When the tank pressure falls to the "cut-in" pressure, the governor allows the compressor to start pumping again. What is the "cut-in" level?
a.
Around 125 pounds per square inch or "psi"
b.
Around 100 pounds per square inch or "psi"
c.
Around 50 pounds per square inch or "psi"
5. Compressed air usually has some water and some compressor oil in it which is bad for the air brake system. Why is it bad for the air brake system?
a.
The water can freeze in cold weather and cause brake failure.
b.
The air can become polluted and impact the function of the brakes.
c.
The presence of oil and water in the tanks may create too much pressure in the tanks.
6. Tractor and straight truck spring brakes will come on when the air pressure drops to what range?
a.
20 to 45 psi
b.
40 to 85 psi
c.
5 to 15 psi
7. When the spring brakes are on, what should you not do?
a.
Push the brake pedal down.
b.
Put on the parking brakes.
c.
Honk the horn.
8. A dual air brake system has two separate air brake systems which use a single set of brake controls. True or False?
a.
True
b.
False
9. What are the maximum leakage rates?
a.
If the air pressure falls more than 3 psi in one minute for single vehicles, then the air loss rate is too much.
b.
If the air pressure falls more than 30 psi in one minute for single vehicles, then the air loss rate is too much.
c.
If the air pressure falls more than 50 psi in one minute for single vehicles, then the air loss rate is too much.
10. What is the controlled braking method?
a.
You apply the brakes as hard as you can without locking the wheels.
b.
You apply the brakes all the way, then release when they lock up, and as soon as the wheels start rolling, repeat.

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About the CDL Driving Test

The Federal Commercial Motor Vehicle Safety Act of 1986 set minimum standards for a Commercial Drivers License in order to reduce accidents involving commercial motor vehicles. To comply with the ... (read more)

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