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Why is the electrical connection between tractor and trailer part of the coupling checks, and what should you verify?
- A.It powers the trailer lights and ABS; verify the plug is fully seated and secured, the cable is supported with slack, and all trailer lights and the ABS lamp check work
- B.The electrical cord only runs the trailer's interior dome light
- C.If the plug is in, no light check is needed
- D.The cord should be stretched tight to keep it off the deck plate
Correct answer
A. It powers the trailer lights and ABS; verify the plug is fully seated and secured, the cable is supported with slack, and all trailer lights and the ABS lamp check work
Why
Without that one plug, the trailer is dark and its ABS is dead, however good its brakes and coupling are. Seating, support, and a full light check close out the connection between the units.
Manual topic: Combination Vehicles - Air Lines and Gladhands · From the Combination Vehicles practice bank (CV-250).