AB Air Brake Test 7 2025

1. Which of the following are major components of the air supply circuit?
2. At what pressure do spring park brakes start to engage if the system air pressure drops?
3. Why is it advised against taking park springs apart?
4. Do the service and park circuits of trailers function the same way as truck and bus circuits?
5. In the context of brake chambers, what does Type 20 typically indicate?
6. What information are air pressure gauges intended to provide in an air brake system?
7. How long is the total stroke for a long stroke chamber?
8. In the context of air brake systems, what does "AD-IS" stand for?
9. Which statement is false about what happens during a brake application?
10. Where does air typically vent during the release of the brakes?
11. What happens when the park control valve is activated?
12. What helps the brakes to disengage more swiftly?
13. What is the primary purpose of the Commercial Vehicle Safety Alliance (CVSA)?
14. At what pressure level is the low-air alarm typically set to activate?
15. How can you manually release spring brakes?
16. At what pressure level does the park brake control valve typically pop out?
17. From which tank is the air pressure for the park circuit delivered?
18. What is the force capacity of the service brakes?
19. What issue may occur with air pressure parking brakes?
20. If the mechanical elements at the ends of the axle, known as foundation brakes, malfunction, what is the likely outcome?
21. What is the function of glad hand couplers?
22. What can be used as an alternative to mechanical spring park brakes for holding foundation brakes in place for the emergency brake?
23. In the event of a failure of the secondary service circuit, which brakes will not operate?
24. What is transported via the air lines that connect to the trailer?
25. Under what circumstances would the dash park control valve be utilized?
26. What is the single tractor air system failure that will result in the service circuit's brakes not functioning during a service application?
27. If there are any indicators that the trailer service brakes aren't functioning and the vehicle needs to be stopped quickly, what should the driver do?
28. During a roadside inspection, what is the consequence if the trailer air supply valve is not working correctly?
29. What is the function of the slack adjuster?
30. When a trailer is not being towed, what should the glad hand couplers have on them?
31. Which statement about emergency braking is incorrect?
32. What is the potential risk of having an extremely strong emergency brake, double the power of spring park brakes?
33. If there's any doubt about the security of the glad hand couplers during coupling, pre-trip, and en-route inspections, what should be the course of action?
34. What potential issue can occur with a tractor that uses coiled plastic air lines?
35. What is the primary function of the tractor protection valve?
36. Why do operators of flat deck haulers run the trailer air lines from the back part of the frame to the landing leg area of the trailer rather than from the back of the cab to the nose of the trailer?
37. In what year did trailers become required to have spring park brakes?
38. When carrying out vehicle inspections, pushing in the trailer air supply valve (red button) with the park control valve (yellow button) pulled out will lead to what outcome?
39. Which components of the tractor's protection system will be checked by enforcement officers during a Level 1 Commercial Vehicle Safety Alliance (CVSA) inspection?
40. In the event of a trailer supply line failure, if the trailer loses traction, what is the likely outcome?
41. According to Commercial Vehicle Safety Alliance (CVSA) roadside inspection standards, what is the minimum acceptable thickness for brake linings?
42. How are malfunctions in the supply circuit identified?
43. Does the trailer supply valve form part of the protection system for the tractor?
44. What can cause the glad hand couplers to leak?
45. What is the function of the service/control line?
46. What step can you take to eliminate contaminants prior to attaching the glad hand couplers?
47. For a trailer with malfunctioning service brakes that needs to be stopped quickly, what should the driver do?
48. What effect will a failure in the park circuit have?
49. Which automatic slack adjuster uses brake application stroke for adjustments exclusively?
50. Why is it recommended to ease off the brake just before the vehicle comes to a stop?
51. What is a significant drawback of detaching the trailer from the tractor?
52. When the slack adjusters turn the S-cams, what happens?