Air Brakes - District Of Columbia Cdl

1 . How is the parking brake released?

By tapping on the brake pedal three times By pushing in the brake control knob By engaging the accelerator By tapping the accelerator twice Click Here Full Cheat Sheet

2 . Pressing and releasing a brake pedal unnecessarily can:

Release air faster than it can be replaced. Add more air to the braking system. Make the brake pedal more sensitive. Create a loud noise. Take a FREE Practice Test Now

3 . Most heavy-duty vehicles use:

Single air brake systems. Dual air brake systems. Triple air brake systems. Quadruple air brake systems. Take a FREE Practice Test Now

4 . Emergency brakes are:

Not required on trucks. Only required on trailers. Required on tractors. Only required when transporting hazardous materials. Take a FREE Practice Test Now

5 . Brakes may get out of adjustment:

If they are too hot. In colder weather. If they are used. If they get wet. Click Here Full Cheat Sheet

6 . What can happen if parking brakes are used in very wet weather with temperatures below freezing?

The brakes will squeak. The brakes may freeze so the vehicle cannot move. The brakes may suddenly release by themselves. The brakes may become too smooth to be used. Take a FREE Practice Test Now

7 . If braking at a speed of 55 mph while driving on dry pavement, the brake lag can add ____ to your vehicle's total stopping distance.

32 feet 15 feet 50 feet 10 feet Take a FREE Practice Test Now

8 . 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. Take a FREE Practice Test Now

9 . All air tanks must include:

A drain valve. A lock. A trap door. A warning sticker. Click Here Full Cheat Sheet

10 . A modulating control valve can control the:

Spring brakes. Landing gear. Air brakes. Anti-lock braking system (ABS). Take a FREE Practice Test Now

11 . The brake pedal is part of which braking system?

The service brake system The parking brake system The emergency brake system The auxiliary brake system Take a FREE Practice Test Now

12 . Service brakes should:

Be tested once a month. Only be tested by a trained mechanic. Be tested before every trip. Take a FREE Practice Test Now

13 . In a vehicle with dual parking control valves, once air pressure is lost and the spring brakes come on:

You will be unable to move the vehicle. A separate air tank can be used to release the spring brakes for a short period of time. You can use the spring brakes to continue driving normally. The air tanks will automatically refill to a safe air pressure level. Click Here Full Cheat Sheet

Study tip: Reduce your study time from hours to minutes with a DMV exam “Cheat Sheet” 99.2% of people who use the cheat sheet pass the FIRST TIME Click Here Full Cheat Sheet

14 . When traveling down a steep downgrade, the best way to use your brakes is to:

Ride the brakes all the way down the hill. Apply the brakes for a few seconds, then release the brakes for a few seconds. Continue to repeat these steps as you travel down the hill. Apply the brakes only near the bottom of the downgrade. Apply consistent pressure to the brake pedal all the way down the hill. Take a FREE Practice Test Now

15 . If a vehicle has air brakes, the air compressor drive belt should be checked before each drive. In what condition should the belt be?

Loose Tight Cracked Bumpy Take a FREE Practice Test Now

16 . To use the stab braking method, you should:

Apply the brakes completely until the wheels lock up, release the brakes until the wheels start rolling, then repeat the process. Apply the brakes about halfway, but allow the wheels to keep rolling. Apply the brakes completely until the wheels lock up and the vehicle stops. Apply the emergency brake until the vehicle starts to slow. Take a FREE Practice Test Now

17 . During a walk-around inspection, ensure there are no cracks on the brake drums that are more than ____ of the width of the friction area.

One half One quarter One third One tenth Click Here Full Cheat Sheet

18 . To make a stop in a vehicle using air brakes, the driver should:

Press down the brake pedal. Lift the brake pedal toward them. Push in the brake knob. Pull out the brake knob. Take a FREE Practice Test Now

19 . When the spring brakes are activated in a vehicle with air brakes, you should never:

Turn on the lights. Turn the vehicle off. Push the brake pedal down. Open the trailer doors. Take a FREE Practice Test Now

20 . Emergency brakes:

Are not required on trucks. Are only required on trailers. Are required on tractors. Are optional. Take a FREE Practice Test Now

21 . When inspecting your brakes, a slack adjuster should move ____ from where it is attached to the push rod.

At least three inches More than two inches Up to five inches No more than one inch Click Here Full Cheat Sheet

22 . Air tank drains:

Allow rain water to enter air tanks. Are used to drain water and oil from air tanks. Should never be opened. Must remain open while driving. Take a FREE Practice Test Now

23 . What should happen if the air pressure in the braking system's air tanks falls below 60 psi?

The warning light will come on. The vehicle will not shift out of gear. The front lights will flash. The steering wheel will lock up. Take a FREE Practice Test Now

24 . What does the air compressor governor do?

Controls when the air compressor pumps air into the air storage tanks. Controls how quickly air leaves the air storage tanks. Controls the temperature of the air entering the air storage tanks. Controls the temperature of the air leaving the air storage tanks. Take a FREE Practice Test Now

25 . A low air pressure warning signal should activate:

When tank pressure falls below 120 psi. When tank pressure falls below 60 psi. When tank pressure falls below 10 psi. When tank pressure falls below 5 psi. Click Here Full Cheat Sheet