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 Indiana 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

1. If the spring brakes are activated, you should never:

Push down the brake pedal.

Open the hood.

Release air from the air storage tanks.

Open the door to the cab.

Never apply the brake pedal if your spring breaks are activated. Brakes can be damaged if they are subject to both springs and air pressure.

2. If the spring brakes are on, you should:

Not use the brake pedal.

Press the accelerator.

Move the steering wheel.

Be especially careful because the brakes may fail.

You should not apply the brake pedal if the spring brakes are activated. The brakes could be damaged if they are subjected to the force of air pressure and the springs at the same time.

3. 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.

4. In a dual air brake system, a leak in one system:

Always means there are leaks in both systems.

May not affect the other system.

Is not something to worry about.

Will also affect the other system.

A dual air brake system is made up of two separate air brake systems. If there is an air leak in one system, it may not affect the other.

5. How is the parking brake released?

By tapping the brake pedal three times

By pushing in the brake control knob

By starting the vehicle

By tapping the accelerator twice

In vehicles with air brakes, the parking brake is controlled by a knob. The knob is pulled out to apply the brakes, and pushed in to release them.

6. In a dual air brake system:

Each system has separate air tanks, hoses, and lines.

The systems share air tanks, but each has its own separate hoses and lines.

Each system uses the same lines and hoses.

One system is the main braking system and a second system is ready to be used if the first one fails.

A dual air brake system is made up of two separate air brake systems. The systems share a single set of brake controls, but each has its own air tanks, hoses, and lines.

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