ON Air Brake Test 2 2025

1. The hand valve of a tractor-trailer
2. In a vehicle equipped with air brakes, what does the governor control?
3. Polarized gladhands on a tractor
4. ln vehicles with three dash-mounted push-pull valve knobs, how are the valve knobs usually coloured?
5. If there is a loss of pressure in the trailer supply line, you would expect the trailer brakes to be applied and
6. If the air pressure reaches 150 psi, the safety valve will open. Where is the safety valve located?
7. The low air warning device must activate by the time that tank air pressure falls to
8. Under Ontario law, tank air pressure must not drop below _______ while the vehicle is in operation.
9. Minimum governor cut-out pressure is
10. When you test the system air-loss rate of a bus or straight truck, the maximum acceptable leakage rate is 3 psi within
11. Maximum governor cut-out pressure is
12. When you test the system air-loss rate, the maximum acceptable leakage rates per minute for a straight truck, a tractor pulling one trailer, and a tractor pulling two trailers are
13. With the engine idling at _________, air pressure must rise from 85 to 100 psi within two minutes.
14. Minimum governor cut-in pressure is
15. The governor cut-in pressure is normally _________ below the cut-out pressure.
16. Air pressure must rise _____________ with the engine idling at 600–900 rpm within 2 minutes.
17. Before starting the air brake practical test, make sure that air pressure is at least
18. The spring brakes will start to apply when the air pressure falls below
19. A tractor-trailer with one trailer will fail the air-loss rate test if the loss rate exceeds
20. The trailer air supply valve will close automatically if air pressure in the trailer supply line drops to
21. A tractor-trailer with two trailers will fail the air-loss rate test if the loss rate exceeds
22. Before testing the low air pressure warning device, make sure that air pressure is at least
23. The air-loss rate test can be performed only when
24. Air compressors can either be driven by the engine belt and pulleys or
25. The spring brake test is passed if the vehicle
26. Different sizes of brake chamber on the same axle can cause
27. To test the air brakes, the vehicle should be parked
28. In a drum brake, the brake linings are attached to
29. Where is the air dryer located?
30. Which of the following are major components of the air supply circuit?
31. When draining the air tanks, you observe excessive oil coming out of the supply tank. Which of the following is most likely to be faulty?
32. You can usually make a normal stop by applying no more than
33. The coil spring in most spring parking brake chambers can exert a force of
34. The spring brake in a certain Type 30/30 brake chamber can exert a force of 2,200 pounds. Which of these choices is the least air pressure needed to release the spring brake?
35. In the air service circuit, there is a double (two-way) check valve connected to the primary and secondary service tanks. What does this valve do?
36. In which of the following situations should a spring parking brake chamber be caged?
37. Wedge brakes are designed to be
38. Where are the air brake chambers located?
39. What does an ABS system do?
40. When you are going at twice the speed, your service brakes will need to work _________ to stop your vehicle.
41. What is the most frequent reason for placing a commercial vehicle out of service?
42. How can you check whether the trailer spring brakes have activated?
43. Which of these vehicles is most likely to be equipped with air brakes?
44. Where is the air pressure gauge for the service tanks?
45. Which colour is the trailer supply line?
46. What can cause the air pressure in the air brake system to drop?
47. How do you apply the parking brakes?
48. Your vehicle's air compressor is belt driven. How do you check for correct belt tension?
49. Which of these is not a part of a drum brake?
50. When brakes become overheated, they also become