Air Brakes Test

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Brake drums...

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When the low pressure warning is activated, you should...

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When the safety valve releases air it means that...

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In a single vehicle with a fully charged air system, air pressure loss (after the initial drop and brake applied) should be less than...

5 / 70

The service brake system...

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Your vehicle's single brake system needs adjustment if...

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Some air brake systems have an alcohol evaporator which helps...

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Air tanks should be drained...

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The safety valve in the air compressor tank is set to open at...

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Compressed air is stored...

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The Air Compressor Governor controls...

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A dual air brake system...

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An emergency brake...

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To check the slack adjusters on S Cam brakes, you should...

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To test the low pressure warning signal, you should do all BUT the following...

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With dual air systems, the air pressure should build...

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A fully charged air system typically has ____ psi.

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To test the air leakage rate you should...

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When testing air leakage rates for combination vehicles (before applying the brake pedal), air brake systems should not lose air faster than...

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To check the air compressor governor "cut in" and "cut out" pressures...

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Air tanks should be drained...

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Fanning air brakes...

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If your air compressor stops working...

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The governor allows the air to start pumping again when it reaches the cut in level, or around...

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You should not use the parking brakes...

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The brake drums or discs...

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Slack adjusters...

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To determine if slack adjusters need adjustment...

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An air tank is equipped with a drain valve to remove...

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The governor stops pumping air when it reaches the "cut out" level, or around...

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Air loss in a straight truck or bus should not be more than ____ with the engine off and the brakes released.

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To make an emergency stop with air brakes, using the stab braking method, you should:

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You should know that your brakes are fading when:

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To check the free play of manual slack adjusters on s-cam brakes you should:

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If the air compressor should develop a leak, what keeps the air in the tanks?

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When driving down a long steep hill you should:

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The brake system that applies and releases the brakes when the driver uses the brake pedal is the:

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The most common type of foundation brakes found on heavy vehicles is the:

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Vehicles with air brakes must have:

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The driver must be able to see a warning that is given before air pressure in the service air tanks falls below:

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If your vehicle has an alcohol evaporator, every day during cold weather you should:

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During normal driving, spring brakes are usually held back by:

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Air braking takes more time than hydraulic braking because air brakes:

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In air brake vehicles, the parking brakes should be used:

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The brake pedal in an air brake system:

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If your truck or bus has dual parking control valves it means that you can use pressure from a separate tank to:

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A straight truck or bus air brake system should not leak at a rate of more than ____ PSI per minute with the engine off and the brakes released.

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If your vehicle has an alcohol evaporator, it is there to:

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If you must make an emergency stop, you should brake so that you:

50 / 70

Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?

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When you apply pressure to the brake pedal, you are...

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The air compressor is connected to the engine through...

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Which type of brake is the most common in commercial vehicles?

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An application pressure gauge...

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All vehicles with air brakes are required to have a low pressure warning signal. This could be...

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To test your service brakes you should...

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Stab braking occurs when you...

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Air brakes take longer to stop than hydraulic brakes because...

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The proper way to go down long grades is to...

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You should avoid using the parking brake...

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Modern air brake systems combines three different systems. The are the service brakes, the parking brakes and the:

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Oil and water usually collect in compressed air tanks. If you do not have an automatic tank drain, when should you drain the air tanks?

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Why drain water from the compressed air tanks?

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Air brake equipped vehicles must have:

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What can legally hold a parking or emergency brake in position for a truck, truck tractor or bus?

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Which of the following makes the total stopping distance for air brakes longer than that for hydraulic brakes.

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Of the choices below, the first thing to do when a low air pressure warning comes on is:

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The braking power of the spring brakes:

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The air compressor governor controls:

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The application pressure gauge shows the driver how much pressure:

The air brakes endorsement applies to applicants who wish to drive a vehicle with air brakes in Class A, B, or C CDL. To drive a vehicle with air brakes, you must pass the air brake test.

There are two parts to the air brake endorsement test – the written and the practical part. The written portion consists of 20 to 25 multiple-choice questions; this test is administered on a computer. The number of questions might vary depending on the state. Usually it is 20-25 questions. The pass mark for the written exam is 80%. Some of the important contents for the written exam includes:

  • Components of an air brake system and dual air brakes.
  • Inspection of the air brake system.
  • The safe use of air brakes.

For first-time CDL drivers, the knowledge exam is included in the skill test. Those adding an endorsement to their CDL will have to schedule their skill test through their local licensing office. The essence of the practical exam is to ensure that you can safely use air brakes.

To pass the practical test (skills test), you will have to demonstrate that you are good at:

  • Using appropriate pressure for different tasks
  • Building air pressure
  • Releasing brakes
  • Testing low air and,
  • Gauging air pressure

Take this CDL practice test now to prepare for the actual air brakes test.