TX CDL Combination 1

Question 1

What is the correct way for air valves when testing the trailer service brakes only?

Answer 1

Service brake: off; Parking brake: off; Trailer air supply: in/open; Trolley: applied

Question 2

You are coupling a semi-trailer to your tractor but have not yet backed under. The trailer is at the right height when:

Answer 2

The trailer will be raised slightly when the tractor is backed under it

Question 3

What is correct for the air valves when testing the trailer spring/parking brakes only?

Answer 3

Service brake: off; parking brake: off; trailer air supply: out; trolley: released

Question 4

Your emergency air line breaks or gets pulled apart while you are driving. The loss of pressure will cause the:

Answer 4

Emergency trailer brakes to come on

Question 5

You supply air to the trailer tanks by:

Answer 5

Pushing in the trailer air supply valve

Question 6

There are two things that a driver can do to prevent a roll over. They are: (1) keep the cargo as close to the ground as possible; and (2):

Answer 6

Go slowly around turns

Question 7

You are coupling a semi-trailer to your tractor but have not backed under. The trailer is at the right height when:

Answer 7

The trailer will be raised slightly when the tractor is backed under it

Question 8

As part of your vehicle inspection test, if your vehicle is equipped with air brakes and has a trailer, you will inspect the air connections between the truck or tractor and the trailer. Make sure that the _______ are locked in place and free of damage or air leaks.

Answer 8

glad hands

Question 9

If your test of the tractor protection valve is successful,

Answer 9

the tractor protection valve control (trailer air supply control) will pop out or go from “normal” to “emergency.”

Question 10

You should not use the trailer hand brake to straighten out a jackknifing trailer, because

Answer 10

the brakes on the trailer wheels caused the skid in the first place.