Chapter 10a: Inspecting Air Brake System Operation

The Ontario air brake test includes a crucial chapter: “Inspecting Air Brake System Operation.” This section focuses on verifying that the entire air brake system functions properly during regular use.

Ontario Air Brake Test - Chapter 10a: Inspecting Air Brake System Operation

1 / 40

When does the vehicle fail the system air-loss rate test?

When there is no pressure drop at all

When the pressure drop exceeds the value specified for that vehicle

When the test lasts less than one minute

When pressure drops only on the secondary gauge

2 / 40

What is the maximum allowable time for pressure to build from 587 kPa (85 psi) to 690 kPa (100 psi)?

Three minutes or less

One minute or less

Five minutes or less

Two minutes or less

3 / 40

What component controls the cut-in and cut-out pressures in an air brake system?

The relay valve

The foot valve

The air-compressor governor

The air dryer

4 / 40

Under Ontario law, what is the status of operating a vehicle with governor settings outside prescribed limits?

It is allowed with reduced speed

It is allowed under supervision

It is allowed only in a yard

It is prohibited

5 / 40

In the build-up time test, what is the end pressure at which timing stops?

621 kPa (90 psi)

587 kPa (85 psi)

552 kPa (80 psi)

690 kPa (100 psi)

6 / 40

Why must the vehicle be parked on level ground before conducting an air brake inspection?

To prevent the vehicle from rolling during the inspection

To make the gauges easier to read

To cool the air compressor

To improve fuel economy

7 / 40

What is not considered in the air-loss rate test?

The initial pressure drop when the brakes are first applied

The engine rpm

The type of vehicle

The final pressure reading after one minute

8 / 40

How do you determine the cut-out pressure during the governor test?

Pump the brakes until the warning light comes on

Turn the engine off and observe pressure drop

Open the drain valves and time the discharge

Run the engine until pressure stops climbing and note the maximum level

9 / 40

What is the maximum allowable air loss for a straight truck, tractor, or bus?

14 kPa (2 psi) per minute

21 kPa (3 psi) per minute

28 kPa (4 psi) per minute

41 kPa (6 psi) per minute

10 / 40

What is the minimum allowable actual cut-in pressure?

380 kPa (55 psi)

414 kPa (60 psi)

690 kPa (100 psi)

552 kPa (80 psi)

11 / 40

Before performing the system air-loss rate test, what must be done with the spring brakes?

They must be applied

They must be caged

They must be released

They must be half-applied

12 / 40

What does the Ontario Highway Traffic Act say about operating a vehicle that fails to build air pressure within the prescribed time?

It is permitted only with a permit

It is prohibited

It is allowed if the vehicle is empty

It is allowed only on secondary roads

13 / 40

What does the Ontario Highway Traffic Act say about operating a vehicle with excessive air loss rate?

It is allowed only with a special permit

It is allowed under 40 km/h

It is prohibited

It is allowed for maintenance trips

14 / 40

When is it safe to leave the driver’s seat or get under a vehicle during inspection?

When air pressure is above 621 kPa (90 psi)

Only when spring brakes are applied or wheels are securely blocked

Whenever the transmission is in neutral

Whenever the engine is off

15 / 40

When does the vehicle fail the low air-pressure warning device test?

When it activates above 690 kPa (100 psi)

When the primary gauge alone shows a warning

When the device does not activate or activates below 380 kPa (55 psi) on either gauge

When the device activates at or above 380 kPa (55 psi)

16 / 40

When does the vehicle fail the air-pressure build-up time test?

When pressure build-up time exceeds two minutes

When pressure build-up time is less than one minute

When only one gauge increases

When pressure does not drop quickly

17 / 40

What is the maximum allowable actual cut-out pressure?

552 kPa (80 psi)

621 kPa (90 psi)

1000 kPa (145 psi)

690 kPa (100 psi)

18 / 40

What must drivers be alert for that indicates possible air brake system leaks?

Unexplained pressure loss in air tanks when brakes are not used

Steering wheel vibration

Engine coolant temperature changes

Increased fuel consumption

19 / 40

Under Ontario law, what is the status of operating a vehicle with a defective low air-pressure warning device?

It is prohibited

It is allowed if the driver is careful

It is allowed only without a trailer

It is allowed for short distances

20 / 40

When does the vehicle pass the governor setting test?

When cut-in is exactly 552 kPa (80 psi)

When cut-in/out are any values but consistent

When cut-in/out are within manufacturer range, cut-out < 1000 kPa (145 psi), and cut-in > 552 kPa (80 psi)

When cut-out is exactly 1000 kPa (145 psi)

21 / 40

When is the air brake system considered defective regarding governor settings?

When cut-out is below 690 kPa (100 psi)

When both cut-in and cut-out are the same

When cut-in is above 1000 kPa (145 psi)

When cut-out is above 1000 kPa (145 psi) or cut-in is below 552 kPa (80 psi)

22 / 40

What is the maximum allowable air loss for a tractor with two or more trailers?

28 kPa (4 psi) per minute

41 kPa (6 psi) per minute

55 kPa (8 psi) per minute

21 kPa (3 psi) per minute

23 / 40

At approximately what pressure do most low air-pressure warning devices activate?

Above 552 kPa (80 psi)

Exactly 621 kPa (90 psi)

Above 414 kPa (60 psi)

Below 380 kPa (55 psi)

24 / 40

At what minimum pressure must the low air-pressure warning device activate, or it is considered defective?

621 kPa (90 psi)

552 kPa (80 psi)

380 kPa (55 psi)

414 kPa (60 psi)

25 / 40

In the build-up time test, from what start pressure do you begin timing?

587 kPa (85 psi)

690 kPa (100 psi)

552 kPa (80 psi)

621 kPa (90 psi)

26 / 40

When does the vehicle pass the low air-pressure warning device test?

When the device activates at any pressure

When the device activates below 380 kPa (55 psi)

When only the primary gauge shows activation

When the device activates at or above 380 kPa (55 psi) on both primary and secondary gauges

27 / 40

What must you do before starting any air brake inspection on a vehicle?

Rely on transmission alone to hold the vehicle

Leave the engine on and transmission in gear

Park on level ground, apply spring brakes, and chock/block the wheels

Park on any surface, apply only the parking brake

28 / 40

When does the vehicle pass the system air-loss rate test?

When pressure stays exactly the same

When the pressure drop is greater than the specified value

When the pressure drop is equal to or less than the specified value for that vehicle

When only one gauge shows a drop

29 / 40

What indicates that the air compressor has reached cut-out pressure on a vehicle with an air dryer?

The service brake lights turning on

A flashing light on the dash

A drop in engine rpm

The air dryer exhaust cycle

30 / 40

How do you determine the cut-in pressure during the governor test?

Watch for when the warning device turns off

Apply the parking brake and see when it holds

Shut off the engine and see when pressure stabilizes

Press and release the brake pedal to lower pressure, then note when pressure begins to rise

31 / 40

How do you lower air pressure when testing the low air-pressure warning device?

Turn the engine off and wait

Pump the parking brake

Open the drain valves

Repeatedly press and release the brake pedal

32 / 40

During the air-loss rate test, what do you do with the brake pedal?

Pump it repeatedly for one minute

Do not touch it at all

Press and hold it fully applied for one minute

Press it halfway down

33 / 40

Approximately how much lower is the cut-in pressure setting than the cut-out pressure setting?

138 to 173 kPa (20 to 25 psi)

345 kPa (50 psi)

200 to 250 kPa (30 to 35 psi)

55 to 70 kPa (8 to 10 psi)

34 / 40

What must be the status of the air brake system pressure before the air-loss rate test?

Within its normal operating pressure range

Exactly 690 kPa (100 psi)

At zero kPa

Below 380 kPa (55 psi)

35 / 40

What is the maximum allowable air loss for a tractor and trailer combination?

7 kPa (1 psi) per minute

28 kPa (4 psi) per minute

41 kPa (6 psi) per minute

21 kPa (3 psi) per minute

36 / 40

To begin the air-pressure build-up time test, to what level must system pressure be reduced?

Below 380 kPa (55 psi)

Below 414 kPa (60 psi)

Below 552 kPa (80 psi)

Below 621 kPa (90 psi)

37 / 40

During the low air-pressure warning test, what must be turned on?

The ignition switch

The headlights

The engine brake

The hazard flashers

38 / 40

What is the first step before testing the air-compressor governor settings?

Disconnect the trailer

Drain all air tanks completely

Properly secure the vehicle and release the spring brakes

Turn off the ignition

39 / 40

To test the low air-pressure warning device, from what minimum pressure must you begin the test?

Above 414 kPa (60 psi)

Above 621 kPa (90 psi)

Above 380 kPa (55 psi)

Above 552 kPa (80 psi)

40 / 40

During the air-pressure build-up test, what engine speed is required?

600 to 900 rpm

Engine off

Above 1,200 rpm

Idle at 400 rpm

Your score is

Drivers must check the air pressure build-up rate, monitor warning devices, and test the service and parking brakes for responsiveness. The inspection also involves ensuring there are no unusual noises or delays when applying the brakes. Understanding how to identify operational issues is essential for both passing the test and maintaining road safety. Mastery of system operation checks prepares drivers to detect and address problems before they lead to brake failure.