FREE CDL Combination Vehicles Practice Test Online | Alabama 2024 Page 3 of 3
Train for FREE online with our Alabama CDL combination vehicle test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a AL combination license in 2021, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that DMV requirements for issuing a combination license may vary from state to state.
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15 . Place the trailer air supply control in its "emergency" position to test:
Be sure to test the trailer emergency brakes before beginning a trip. After ensuring that the trailer rolls freely, you can test the emergency brakes by pulling out the trailer air supply control, or placing it in the "emergency" position. Pull forward slightly with the tractor and make sure the trailer does not move.
16 . During a trip, which shut-off valves should be open?
No shut-off valves should be open.
When starting a trip, be sure that all shut-off valves are in the open position, except for the last valves on the rear trailer. It is important that air reaches the brakes on all trailers and that the air is not able to escape from the back of the vehicle.
17 . Trailers built before ____ are not required to have spring brakes.
Trailers built before 1975 are not required to have spring brakes. When parking a trailer without spring brakes, be sure to use wheel chocks to prevent the trailer from rolling.
18 . When backing up while coupling a trailer, the tractor should be positioned:
When backing up to couple a trailer, you should position the tractor directly in front of the trailer. Trying to couple while backing at an angle could cause the trailer to move and the landing gear to break.
19 . If your trailer goes off course while you are backing, you should:
Turn the steering wheel all the way to the left until the trailer straightens out.
