2024 HI CDL Practice Test: Double and Triples - Test 2
Based on
2024 HI CDL Handbook
13. What do you need to do to check that air flows to all trailers?
A
Wait for air pressure reach normal.
B
Push in the red "trailer air supply" knob
C
All of the listed answers.
D
Use the tractor parking brake.
E
Open the emergency line shut-off valve at the rear of the last trailer.