Based on 2023 ON commercial driver's license manual Instant feedback
Get ready for Ontario Commercial Air Brake Test 9. This exam will take you through the ins and outs of emergency braking techniques. With 50 questions, we've meticulously curated this test to ensure it covers all the material you'll face in the real deal. Start practicing now to get ahead.
Where should ABS indicators typically be mounted on trailers?
Who can be charged for driving a vehicle with defects or for failing to conduct the required inspections?
Which statement is incorrect? Drivers are expected to identify brake components that are...
To ensure balanced braking, how should slack adjusters on each side of an axle be?
Which brake hoses and tubes are the most prone to damage?
If all other air brake chambers function but one has a defect, is it lawful to drive the vehicle on any road or highway?
When must air compressors always be inspected?
Slack adjusters usually have how many holes designed for pushrod attachment?
Which statement is incorrect? Damage or deterioration to brake hoses and tubes may be in the form of...
What typically influences the setting of the governor pressure?
At what point do the air pressure gauges cease to rise?
The low air pressure warning device should be tested at _______ or higher.
What is the maximum acceptable rate of air loss for a tractor and trailer combination?
What should occur after the regular draining of air tanks?
How long should you observe air pressure readings to test the air loss rate of a brake system?
To test air pressure build up time, what should be the speed of the engine?
A vehicle passes the system air-loss rate test when the drop in pressure is...
The vehicle passes the test when the device activates at or above what psi on both primary and secondary air tank gauges?
Whenever what event occurs, a trailer's spring brakes must automatically engage?
Which of the following is not one of the procedures for testing air-compressor governor settings?
Even with regular drainage, a prominent amount of moisture being discharged from the supply tank is...
Which of the following does not apply when testing a tractor (towing vehicle) protection valve?
The low air pressure warning device fails if it does not activate or if it turns on when pressure is below
What is the maximum acceptable air loss rate for a straight truck, tractor, or bus?
Any oil found in any air tank except the supply tank should be
Which of the following is not a procedure for testing low air-pressure warning devices?
When the engine is idling between 600 and 900 rpm, how long should it take for the air pressure to rise from 85 to 100 psi?
In testing the low air-pressure warning device, pressure in the system must be reduced to the point where the device activates or at what psi, whichever is higher?
The vehicle fails the test if the low air pressure warning device does not activate or activates when pressure is below what psi on both primary and secondary air tank gauges?
For the test of air-pressure build-up time, the system air pressure should be reduced to below
The vehicle fails the system air-loss rate test when...
What poses a concern if oil is discovered in any air tank, apart from the supply one?
The range of the system pressure is controlled by what?
The air brake system should be considered defective if the cut-out pressure is
What's the maximum acceptable air loss rate for a tractor towing two or more trailers?
When the tractor protection valve is tested, the tractor passes the test when...
What isn't a step when testing spring (parking and emergency) brakes?
What's the effect of compressor cut-in during air compressor governor settings test?
What isn't a required step when testing the automatic activation of trailer spring brakes?
Which of the following is not correct? You should inspect brake chambers at each wheel for...
Is it possible to fit brake-stroke indicators to brake linkage?
If a driver is found to be operating a vehicle with defects, what will happen to the vehicle?
You are testing the tractor protection valve with a trailer that lacks an anti-compounding valve. What should you do?
Certain body designs and suspensions of some vehicles may hinder safe access to air tanks and drains. What should be done in such cases?
When checking the automatic application of trailer spring brakes, if you're unsure whether they have been applied, what should you do?
Which of the following is not a requirement for a brake inspection of a truck in a practical examination? You must know your vehicle's brake chamber size and type and bring which of these?
Which of the following is not a mandatory step when testing the air-tank drain valves?
A brake chamber pushrod is normally labeled with what?
What is the most common size for a brake chamber?
When testing the tractor protection valve, from where should you note if air is escaping?
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