|
To make the air brakes work more effectively.
|
|
|
To temporarily release the spring brakes.
|
|
|
To charge the brakes on the rear trailer.
|
Iowa CDL Permit Test - Air Brakes
(From the 2021 Iowa CDL driver handbook)
| Number of questions: | 25 |
| Passing score: | 20 |
Directions:
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 answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Iowa 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.
Passing grade —
5 or fewer errors
advertising
1.
In a vehicle with dual parking control valves, a separate air tank can be used:
2.
If using spring brakes when hauling a heavy load, a complete stop will:
|
Be impossible.
|
|
|
Take a long time.
|
|
|
Take a short amount of time.
|
3.
Why do large vehicles use air brakes?
|
Other brake systems squeak too loudly.
|
|
|
Air brakes are very effective systems.
|
|
|
Other braking systems are hard to come by.
|
4.
When leaving a vehicle unattended, a driver should:
|
Always set the parking brake.
|
|
|
Only set the parking brake if the vehicle is parked on a slope.
|
|
|
Deflate the tires by 10 percent.
|
5.
If the spring brakes are on, you should:
|
Not use the brake pedal.
|
|
|
Press the accelerator.
|
|
|
Move the steering wheel.
|
6.
Brake fade is a result of:
|
Brakes being exposed to sunlight.
|
|
|
Brakes being exposed to moisture.
|
|
|
Excessive use of the brakes.
|
Ace Your DMV Written Test
Get your Cheat Sheet Now!
Get your Cheat Sheet Now!
Wait, before you go
Ace your DMV Written Test with our Guaranteed Cheat Sheet.
