Ontario Commercial Drivers License Air Brakes Practice Test 4

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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

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

242 kPs (35 psi)

380 kPa (55 psi)

413 kPa (60 psi)

551 kPa (80 psi)

2 / 20

When brakes become overheated they also become?

Extra efficient

Very hot

None of the above

Dangerously inefficient

3 / 20

What is an ABS system?

Increases braking power

Automatically brakes when needed

Reduces stopping distance

Prevents wheel lock

4 / 20

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

Pull out the control

Press down the pedal

Twist it to the right

Twist it to the left

5 / 20

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

On each wheels brake

Beside the air compressor

Beside the supply tank

On the vehicle dashboard

6 / 20

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

A hole in the supply line

A broken air compressor

All of these

Disconnected supply line

7 / 20

What is a "glad hand"?

A coupling device

A dance move

An emergency supply line

The crank for the trailer legs

8 / 20

Correct belt tension for an air compressor can be determined by

Firm hand pressure

A tight squeeze of the hand

Finger pressure

A karate chop

9 / 20

Why are their two service tanks?

Incase you need more stopping power

For fuel economy

For safety

For efficiency

10 / 20

Cut out pressure level must never exceed __________.

1000 kPa (145 psi)

1138 kPa (165 psi)

862 kPa (125 psi)

690 kPa (100 psi)

11 / 20

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

Sandals and shorts

Steel toe boots, safety glasses, hard hats

Dust mask, safety glasses

Shorts and Crocs

12 / 20

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

Only certified technicians

You can if you are the owner

Your employer

Anyone

13 / 20

What function does the alcohol evaporator perform?

Prevents freezing

Prevents overheating

Prevents moisture build ups in the brake lines

Prevents the system from building up too much pressure

14 / 20

Activation of trailer spring brakes can be checked by?

Pulling the trailer air valve

Gunning it

Applying slight engine power

Rocking the truck back and forth

15 / 20

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

Lining

Drum

Shoe

Rotors

16 / 20

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

A school bus

A pickup truck

A hearse

A compact car

17 / 20

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

Weight of the vehicle

Driving speed

Weight of the driver

Brake adjustments

18 / 20

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

Tire treads

Over weight limits

Sleepy drivers

Air brakes

19 / 20

Which colour represent the trailer supply line?

Yellow

White

Red

Blue

20 / 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?

2 mins

1 min

4 mins

5 mins

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The average score is 89%

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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.