Combination Vehicle Test
Question #1 of 54
Which of the following best describes what the trailer air supply control does?
You pull it out to supply the trailer with air and push it in to shut the air off and put on the trailer emergency brakes.
You push it in to supply the tractor with air and pull it out to supply the trailer with air.
You push it in to supply the trailer with air and pull it out to shut the air off and put on the trailer emergency brakes.
You push it in to supply the trailer with air and pull it out to supply the tractor with air.
The Combination Vehicle CDL Test