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 three or four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Wyoming Driver License Manual for Commercial and Heavy Vehicles. 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
Passing Score

1. Test the low pressure warning signal:

Explanation
It is essential that your low pressure warning light function properly. After allowing the system to charge, you can test the warning signal by rapidly applying and releasing the brake pedal. This will release air from the braking system and the warning signal should come on when pressure drops to a dangerous level.

2. A modulating control valve can control the:

Explanation
A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.

3. The ____ between an air compressor and reservoir tank prevents air from escaping if the air compressor has a leak.

Explanation
A one-way check valve is required to be between an air compressor and the first main reservoir. This valve prevents air from escaping the system if the air compressor develops a leak.

4. On a truck with air brakes, the braking system’s air compressor:

Explanation
In an air brake system, the air compressor pumps air into the air storage tanks. The air compressor is controlled by the air compressor governor.

5. On newer vehicles, how do you put on the parking brake?

Explanation
On newer vehicles with air brakes, the parking brake is controlled by a yellow, diamond-shaped knob. The knob is pulled out to set the brakes, and pushed in to release them.

6. To make a stop in a vehicle equipped with air brakes, the driver should:

Explanation
To make a normal stop in a vehicle that is equipped with air brakes, you should simply press the brake pedal down.
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