Air Brakes Test Illinois (2024) - FREE CDL Practice Test

1. Brake fade results from, and is affected by:

brakes out of adjustment.
excessive heat caused by not relying on the engine braking effect.
excessive heat caused by using the brakes too much.
All of the above.

2. The use of air brakes on a steep downgrade is only a supplement to:

the use of the parking brakes.
the use of the "controlled braking" method.
the braking effect of the engine.
the use of the spring brakes.

3. Too little weight on the driving axles can cause:

4. A dual air brake system:

has two separate air brake systems, which use a single set of brake controls.
has two separate air brake systems, which use two separate sets of brake controls.
has a single air brake system, which uses a single set of brake controls.
has a single air brake system, which uses two separate sets of brake controls.

5. _________ must have a low air pressure warning signal.

Vehicles with air brakes built after 2010
Only vehicles with air brakes built before 2015
All vehicles with air brakes
Vehicles with air brakes built after 2005

6. If you are driving a 30-foot vehicle at 55 mph, you should leave at least _____ between you and the vehicle ahead.

7. With a fully-charged air system, the leakage rates should be less than:

3 psi for single vehicles and 4 psi for a combination of two vehicles.
2 psi for single vehicles and 3 psi for a combination of two vehicles.
5 psi for single vehicles and 4 psi for a combination of two vehicles.
5 psi for single vehicles and 10 psi for a combination of two vehicles.

8. If your ABS malfunctions:

you should immediately come to a complete stop.
the service brake will not work.
you still have normal brake functions.
the parking brakes will not work.

9. When driving in very hot weather, the heat will increase the chances of:

10. A driver distraction is anything that takes your attention away from driving, such as:

AIR BRAKES CDL PRACTICE TEST - ILLINOIS