Ontario Commercial Drivers License Air Brakes Practice Test 1

Commercial Driver HQ is a website focused on helping new commercial drivers in all provinces and territories in Canada.

Our FREE practice tests are designed to help you succeed when it comes time to write the real test.

Each license type has 5 tests to help you study and become familiar with the rules and regulations of commercial driving. The tests are not identical to the license test you will need to pass, but the questions are similar to what you will find on the real deal.

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Created by Commercial Driver HQ

Ontario Air Brakes Practice Test 1

A 20 question practice test to help prepare you for your air brakes knowledge test in Ontario

1 / 20

Test the low pressure alarm with the air pressure above __________.

2 / 20

You test a tractor protection valve by removing the service line and?

3 / 20

How long should it take for the air pressure to rise from 587kPa to 690 kPa after the pressure had fallen below 552 kPa?

4 / 20

Before inspecting for air brake chamber leaks, you must __________.

5 / 20

If brake chambers on opposite side of an axle are different sizes, this may cause?

6 / 20

What is the best way to inspect an air compressor?

7 / 20

When can you adjust your own air brakes?

8 / 20

To measure the time it takes to build up pressure in the air system, the engine should be idling between _______________.

9 / 20

When inspecting your brakes, you must?

10 / 20

When brakes become overheated they also become?

11 / 20

System air loss should be measured by applying the brake for how long?

12 / 20

You should be looking for this when checking your brake chambers?

13 / 20

How much air loss is allowed for a tractor and a trailer when the brakes are engaged?

14 / 20

If the outer layer of an airline is damaged, but the inner layer is ok, what should you do?

15 / 20

When you are testing your spring brakes, the test is considered a success when?

16 / 20

The supply tank should discharge more moisture than any other tank?

17 / 20

To make sure the air tanks are securely attached to the vehicle you should?

18 / 20

What is the most frequent reason a vehicle is removed from service?

19 / 20

Where is the brake lining fastened?

20 / 20

A commercial vehicle with air brakes engaged must not lose air pressure faster than?

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We do our best to keep the questions current and accurate. The testing centres may change the questions on the knowledge tests at any time. Always be prepared for surprises.

Many of the answers to the questions can be found in the driver hand books or learning materials your province provides.

DISCLAIMER: CDHQ is not affiliated with DriveTest or the MTO. These practice tests should not be considered official tests and you are not granted a license for completing them. Our tests are simply a practice tool to help prepare yourself for the real test.