CDL
Courses
LMS
English
English
Ukrainian
Russian
Polish
Login
Home
CDL
Permit
Combination Vehicles #1
Practice Test
Active Practice Session
Combination Vehicles #1
Question 12 of 20
60% complete
Question 12
After you hook up the air lines, but before you back up under the trailer, you should:
A
Disconnect the electrical line.
B
Check the tire pressure on the trailer.
C
Supply air to the trailer system, then pull out the air supply knob.
Select an answer to continue.
This website uses cookies in order to offer you the most relevant information. Please accept cookies for optimal performance.
I Agree