CDL Combination & Air brake Test
1. Tractor Protection Values <Ans> -It keeps air in the tractor in the event the trailer air
leaks
- It is controlled by the trailer air supply valve in the cab
-It will close automatically if air pressure is low
2. If one of the glad hands on your blue air line is missing a seal.. <Ans> You might
end up with a service line air leak.
3. Which one of the following is controlled by the foot brake? <Ans> The Service air
line
4. If you cross your air lines on a new trailer with spring brakes.. <Ans> you won't be
able to release the trailer brakes
5. When you inspect the coupling, check to ensure that.. <Ans> there's a little slack in
the air lines
6. You can damage the landing gear if you.. <Ans> back under the trailer at an angle
7. When traveling under 40 mph, you should follow other vehicles.. <Ans> With a
distance of one second for every ten feet of your vehicle length
8. When uncoupling, it's a good practice to.. <Ans> - couple the glad hands together
1/8
, -couple the glad hands to dummy couplers
-hang the electrical cable with the plug end down
9. The trailer hand valve should be used.. <Ans> Only to test the trailer brakes
10. In order to supply air to the trailer, you must first.. <Ans> Push in the tractor
protection valve
11. The earliest way to notice a trailer skid is.. <Ans> By seeing it in your mirrors
12. Before you begin coupling... <Ans> Check your path for Hazards
13. You should crank the landing gear until.. <Ans> It is as far up as it will go
14. When coupling the trailer, back up slowly until.. <Ans> The fifth wheel just touches
the trailer
15. The trailer should be lowered so that.. <Ans> it's raised slightly when the tractor's
backed under it
16. In order to inspect the coupling you should.. <Ans> use a Flashlight
17. A kingpin is... <Ans> A pin which locks the trailer to the tractor on the fifth wheel
18. The trailer air supply control.. <Ans> Is a red, 8 sided knob
19. The fifth wheel should be checked to see if.. <Ans> There is any damage or missing
parts
It is properly greased
2/8
1. Tractor Protection Values <Ans> -It keeps air in the tractor in the event the trailer air
leaks
- It is controlled by the trailer air supply valve in the cab
-It will close automatically if air pressure is low
2. If one of the glad hands on your blue air line is missing a seal.. <Ans> You might
end up with a service line air leak.
3. Which one of the following is controlled by the foot brake? <Ans> The Service air
line
4. If you cross your air lines on a new trailer with spring brakes.. <Ans> you won't be
able to release the trailer brakes
5. When you inspect the coupling, check to ensure that.. <Ans> there's a little slack in
the air lines
6. You can damage the landing gear if you.. <Ans> back under the trailer at an angle
7. When traveling under 40 mph, you should follow other vehicles.. <Ans> With a
distance of one second for every ten feet of your vehicle length
8. When uncoupling, it's a good practice to.. <Ans> - couple the glad hands together
1/8
, -couple the glad hands to dummy couplers
-hang the electrical cable with the plug end down
9. The trailer hand valve should be used.. <Ans> Only to test the trailer brakes
10. In order to supply air to the trailer, you must first.. <Ans> Push in the tractor
protection valve
11. The earliest way to notice a trailer skid is.. <Ans> By seeing it in your mirrors
12. Before you begin coupling... <Ans> Check your path for Hazards
13. You should crank the landing gear until.. <Ans> It is as far up as it will go
14. When coupling the trailer, back up slowly until.. <Ans> The fifth wheel just touches
the trailer
15. The trailer should be lowered so that.. <Ans> it's raised slightly when the tractor's
backed under it
16. In order to inspect the coupling you should.. <Ans> use a Flashlight
17. A kingpin is... <Ans> A pin which locks the trailer to the tractor on the fifth wheel
18. The trailer air supply control.. <Ans> Is a red, 8 sided knob
19. The fifth wheel should be checked to see if.. <Ans> There is any damage or missing
parts
It is properly greased
2/8
