AB Air Brake Test 2 2025

1. If there is a loss of pressure in the trailer supply line, you would expect the trailer brakes to be applied and
2. If the air pressure reaches 150 psi, the safety valve will open. Where is the safety valve located?
3. The low air warning device must activate by the time that tank air pressure falls to
4. A modern Air Dryer Integrated System (AD-IS) includes which of the following components?
5. Minimum governor cut-out pressure is
6. With an Air Dryer Integrated System (AD-IS), you would expect the air pressure build-up time to be ________ without an AD-IS.
7. Maximum governor cut-out pressure is
8. Can an air brake system include both an air dryer and an alcohol evaporator (injector)?
9. With the engine idling at _________, the air pressure must rise from 50 psi to 90 psi within three minutes.
10. Your vehicle may still be driven if
11. The governor cut-in pressure is normally _________ below the cut-out pressure.
12. With the engine idling at 1,200 rpm, the air pressure must rise _____________ within 3 minutes.
13. Before starting the air brake test procedures, make sure that air pressure is at least
14. The spring brakes will start to apply when the air pressure falls below
15. During a pre-hill inspection, you should check which of the following aspects of the air brake system?
16. The trailer air supply valve will close automatically if air pressure in the trailer supply line drops to
17. Which of the following statements is true?
18. Before testing the low air pressure warning device, make sure that air pressure is at least
19. The air-loss rate test can be performed only when
20. Air compressors can either be driven by the engine belt and pulleys or
21. The spring brake test is passed if the vehicle
22. Different sizes of brake chamber on the same axle can cause
23. To test the air brakes, the vehicle should be parked
24. In a drum brake, the brake linings are attached to
25. Where is the air dryer located?
26. 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?
27. You can usually make a normal stop by applying no more than
28. The coil spring in most spring parking brake chambers can exert a force of
29. Spring parking brakes typically require air pressures of at least _______ to completely release.
30. 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?
31. In which of the following situations should a spring parking brake chamber be caged?
32. Wedge brakes are designed to be
33. Where are the air brake chambers located?
34. What does an ABS system do?
35. When you are going at twice the speed, your service brakes will need to work _________ to stop your vehicle.
36. Which of these significantly decreases the braking force produced at the wheel?
37. Which type of trailer can be towed before the service tanks are full?
38. In determining how well your air brake system works, which is NOT a significant factor?
39. In large commercial vehicles, most air brake systems use automatic valves to
40. Where are a vehicle's air tanks located?
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