Ontario Commercial Drivers License Air Brakes Practice Test 4

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Created by Commercial Driver HQ

Ontario Air Brakes Practice Test 4

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

1 / 20

Which of these is not part of an air brake system?

2 / 20

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

3 / 20

Where is the air pressure gauge for the air brake system?

4 / 20

What is not a factor in how well your air brake system works?

5 / 20

Correct belt tension for an air compressor can be determined by

6 / 20

What is a "glad hand"?

7 / 20

Who can perform adjustments and maintenance on your air brake system?

8 / 20

How do you engage the emergency / parking brake on most air brake systems?

9 / 20

Why are their two service tanks?

10 / 20

What can cause the air pressure in the air brake system to drop?

11 / 20

Which colour represent the trailer supply line?

12 / 20

Activation of trailer spring brakes can be checked by?

13 / 20

What function does the alcohol evaporator perform?

14 / 20

A warning system must alert the driver when the pressure drops below?

15 / 20

When brakes become overheated they also become?

16 / 20

What is an ABS system?

17 / 20

Cut out pressure level must never exceed __________.

18 / 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?

19 / 20

Which of these vehicles would usually have an air brake system?

20 / 20

When inspecting an air brake system, the person inspecting should wear?

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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.