most of us buy into a system that is hooked up to the lights of our pulling unit. no additional fuses or switches.
When I put in new lights I check each light and see if it still works farther down the system.
http://truckyeah.jalopnik.com/did-fault ... 1551319803
I at one time thought of a box that has both male and female trailer plug on it so no mater what plugged in if something was wrong they would blow first.
I am using wires from different past and new harnesses because I am putting on the LED lights I want. Each have ground wires which will go to both the pull unit and the trailer frame.
The Batteries that i use will also be grounded on the trailer frame.
any one have any input on this or words for present and future trailer builders.
Ron