Air Brake Test Practice: Z Endorsement Ontario 2025

Air Brake Test Practice: Z Endorsement Ontario 2025: Try our free Air brake systems technical questions and answers for the Ontario Truck Driver Licence exam. There are a total of 50 multiple choice question answers regarding Air Brake knowledge test.

A practice test for the MTO’s “Z” endorsement for trailer air brake systems. ailer air brake systems. For those upgrading to a truck and trailer equipped with air brakes. Gain the knowledge necessary to operate brake systems safely and detect faults in these systems. Upon successful completion of the written test, participants will take the practical test

Air Brake Test Practice: Z Endorsement Ontario

After successful completion of both tests, you will receive the ‘Z’ endorsement from the Ministry of Transportation. Students must bring proof of (at least) a full ‘G’ license. Air Brakes are used on some medium‐duty and all heavy‐duty vehicles. The air braking system is basically a series of valves forcing compressed air through the system to generate a constant supply of air which is then used to apply the brakes.

Test type	AZ Practice Test Ontario 2025
Licence Type	Commercial Truck Driver
Class	Full G
Province	Ontario
Test type	Sample Practice Test
Total Questions	50 MCQs
Topics Covered	Air Brake Z Endorsement

0 votes, 0 avg

718

Air Brake Knowledge Test

1 / 31

Actual cut-in pressure must never be less than ____ psi?

A) 80 psi

B) 75 psi

C) 70 psi

D) 95 psi

2 / 31

Which of the following braking systems are used on most large commercial vehicles?

A) Air brake systems

B) Air parking brakes

C) Hydraulic brake systems

D) Air-over-hydraulic brakes

3 / 31

Which of the following brake system used compressed air?

A) Cool brake systems

B) Air brake systems

C) Hydraulic brake systems

D) Air padal brake systems

4 / 31

Safety valves normally open at ____ psi.

A) 155 psi

B) 150 psi

C) 140 psi

D) 145 psi

5 / 31

Air pressure is usually measured in ______

A) kiloPascals (kPa)

B) pounds per square inch (psi)

C) kiloPascals (kPa) or pounds per square inch (psi)

D) air per square inch (asi)

6 / 31

Which of the following brake is called service brakes?

A) brakes that are used for parking

B) brakes that are used for emergency braking

C) all of them

D) brakes that are used for normal stopping

7 / 31

What is the function of an Alcohol evaporator?

A) it collect less moisture than the supply or “wet” tank.

B) it reduce the tendency of moisture in the air brake system can freeze

C) it cools the moisture and passes through a drying material

D) if one circuit fails, the other circuit will provide enough brake function to stop the vehicle

8 / 31

To drive a vehicle with ________ braking systems in Ontario, you must have an air brake endorsement on your driver’s licence,

A) Hydraulic brake systems

B) Air-over-hydraulic brakes

C) Air parking brakes

D) Air brake systems

9 / 31

Where the air dryer is located?

A) between the primary and the supply tank

B) between the air compressor and the supply tank

C) between the supply tank and the air compressor

D) between the primary and secondary tanks

10 / 31

How do you prevent too much moisture and oil from collecting?

A) the air tanks must be drained regularly

B) the air dryer must be drained regularly

C) the primary and secondary tanks must be drained regularly

D) the safety valves must be drained regularly

11 / 31

Which of the following chamber contains a flexible rubber disc called a diaphragm?

A) air brake chamber

B) hydro brake chambers

C) spring brake chambers

D) service brake chamber

12 / 31

Which of the following problems can occur if the mixture of moisture and oil that collects in the supply tank passes into the rest of the air brake system?

A) Moisture in the brake system can freeze in cold temperatures and may cause brake failure.

B) Too much moisture and oil collecting in the Air-tanks can reduce the volume of air and may cause brake failure.

C) all of them

D) The mixture of moisture and oil can become corrosive and damage the Air-tank and other system components.

13 / 31

Why Spring brakes are designed?

A) on an emergency to stop your vehicle

B) all of them

C) when your service brakes fail

D) when you are parking your vehicle

14 / 31

When application pressure increases from ____ psi to ____psi, the stroke increases noticeably.

A) 10 psi to 80 psi

B) 5 psi to 50 psi

C) 8 psi to 80 psi

D) 6 psi to 60 psi

15 / 31

What is the minimum air pressure that must be supplied to the spring brake chamber to compress or “cage” the spring to release the spring brakes?

A) 30 psi

B) 40 psi

C) 50 psi

D) 60 psi

16 / 31

What do you mean by low air-pressure warning?

A) all of them

B) means there is a serious air brake system safety hazard

C) means air brake system is failed

D) means there is a minor air brake system safety hazard

17 / 31

Which of the following removes moisture from the air brake system?

A) safety valves

B) alcohol evaporator

C) air pressure gauges

D) air dryer

18 / 31

How the normal pressure range of an air brake system is determined?

A) it is determined by the points where the air compressor is turned on and turned off

B) it is determined by the points where the air compressor is cut-out pressure and cut-in pressure

C) it is determined by the points where the air compressor is turned off and turned on

D) all of them

19 / 31

What is the normal air brake system pressure range?

A) around 95 to 115 psi

B) around 110 to 125 psi

C) around 90 to 110 psi

D) around 100 to 120 psi

20 / 31

Which of the following tank uses two circuits system? (two circuits are referred to as the primary circuit and the secondary circuit.)

A) Dual-Air dryer

B) Dual Air-tank drain valve

C) Two way check valve

D) Dual-service tanks

21 / 31

Which of the following major brake types are used in air brake systems?

A) drum/disc brakes

B) Pedal brake

C) Engine brake

D) Hydraulic brake

22 / 31

Which of the following brake system used the brake fluid?

A) Air brake systems

B) Hydraulic brake systems

C) Auto brake systems

D) Pedal brake systems

23 / 31

How does a break work to stop a moving vehicle?

A) the brake rotors exert pressure on the brake drums

B) the brake shoes exert pressure on the brake drums

C) the brake shoes exert pressure on the brake pads

D) the brake drums exert pressure on the brake pads

24 / 31

Brakes convert the _____ of a moving vehicle into heat.

A) energy

B) air

C) hydraulic

D) all of them

25 / 31

What is compressed air?

A) form of stored compressed air

B) form of stored energy

C) form of stored air

D) form of stored cool air

26 / 31

Which of the following prevents over-pressure of the air brake system?

A) Air dryer

B) Safety valves

C) Air pressure

D) Alcohol evaporator

27 / 31

Which of the following component causes the compressor to stop pumping air and also cause the compressor to start pumping air again if required?

A) central governor

B) compressor monitor

C) air brake monitor

D) governor

28 / 31

During a trip, you have noticed that the brakes overheat due to overuse or improper adjustment. What you must do?

A) all of them

B) do not press the brake harder

C) stop and allow them to cool before proceeding

D) use engine brake instated of paddle brake

29 / 31

Actual cut-out pressure must never be higher than _____ psi?

A) 155 psi

B) 125 psi

C) 145 psi

D) 115 psi

30 / 31

Which of the following method may use by a technician to temporarily disable a spring brake chamber when it is fail?

A) spring in spring brake method

B) manual caging method

C) caging bolt method

D) all of them

31 / 31

What is the function of an air pressure gauge?

A) let you know how much air pressure is in the air brake system

B) All of them

C) let you know how much air pressure is in the secondary tanks

D) let you know how much air pressure is in the primary tanks

Your score is

The average score is 70%