Question

What should you do after connecting the airlines but before backing under the trailer?

A) Supply air to the trailer system, and then pull the air supply knob
B) Make sure that the trailer brakes are off
C) Walk around the rig to make sure it is clear

Answer 1

Before backing under the trailer, you should supply air to the trailer system, make sure the trailer brakes are off, and walk around the rig to ensure it is clear.

Step-by-step explanation:

Before backing under the trailer, there are a few steps you should take.

1. First, supply air to the trailer system by pulling the air supply knob. This will ensure that the trailer's brakes and other systems are powered and functioning properly.
2. Next, you should make sure that the trailer brakes are off. This can be done by checking the brake control valve and ensuring it is in the released position.
3. Finally, it is important to walk around the rig to make sure it is clear. Look for any obstacles or hazards that could impede your backing maneuver.

By following these steps, you can ensure a safe and smooth backing maneuver under the trailer.