Instructions

Air Brakes

This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a written test. The test consists of 25 multiple choice.. Read More

This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a written test. The test consists of 25 multiple choice questions. Each question has four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Colorado Commercial Driver License Manual. Questions come from the chapter covering: Air Brakes. The Air Brakes endorsement may be used with the Class A, B or C CDL.

Number of Question 25

Passing Score 20

19. When using the controlled braking method in an emergency situation, you should:

Apply the brakes as hard as possible without locking the wheels.

Apply the brakes with about half of your usual force.

Apply the brakes so the wheels lock.

Apply the brakes with minimal pressure.

The controlled braking method for emergency stops involves applying the brakes as hard as you can without locking the wheels. Keep steering wheel movements small when braking in this way.

20. Which type of brakes do most heavy-duty vehicles have?

Air brakes

Solid brakes

Liquid brakes

Gravity brakes

For safety, most heavy-duty vehicles are equipped with dual air brake systems.

21. The emergency brake system uses:

Only parts of the parking brake system.

Only parts of the service brake system.

Parts of both the parking and service brake systems.

Only parts unique to the emergency brake system.

In an air brake system, there are three different braking systems: a service brake system, a parking brake system, and an emergency brake system. The emergency brake system uses parts of both the parking and service brake systems.

22. The air storage tanks:

Hold only enough air for one braking cycle.

Hold enough air for brakes to be used several times if the compressor stops working.

Do not hold air unless there is an emergency.

Hold enough air for more than 1,000 braking cycles.

In an air brake system, the air storage tanks hold enough air for brakes to be used several times if the compressor stops working.

23. The application pressure gauge:

Shows how much air pressure is being applied to the brakes.

Shows the temperature of air being used in the braking system.

Shows the pressure of the air coming from the compressor.

Shows the number of times the brakes have been used.

In an air brake system, the application pressure gauge shows how much air pressure is being applied to the brakes. Not all vehicles with an air brake system have this gauge.

24. When only the tractor is equipped with an Anti-Lock Braking System (ABS):

There is a decreased risk of jackknifing.

There is an increased risk of jackknifing.

The brakes will not work as effectively as they would without ABS.

The brakes will become more sensitive.

If a tractor is equipped with an Anti-Lock Braking System (ABS) but the trailer is not, the risk of jackknifing will be reduced and the driver should still be able to maintain steering control. If only the trailer is equipped with ABS, it is less likely that the trailer will swing out to one side.

25. When you press the brake pedal in a vehicle with S-cam brakes, air pressure pushes out the rod and moves the:

Slack adjuster.

Axle.

Brake drum.

Alcohol evaporator.

When pressing the brake pedal in a vehicle with S-cam brakes, air will enter the brake chambers. The added air pressure will push out the rods and move slack adjusters, twisting the brake camshafts.

Grade This Section

See the exact questions that will be on the 2024 Colorado DMV exam.

99.2% of people who use the cheat sheet pass the FIRST TIME

Alexa shares with us how she went in for her Class A permit and decided to get her Hazmat endorsement as a bonus!

Mark shares his feedback on his Class A CDL Cheat Sheet

Click Here
Full Cheat Sheet Unlock Your Exclusive Cheat Sheet!