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