Join Date: Dec 2011
Location: Arlington, tx, usa
Re: Bustech Trailer Wiring
"Its just an extra wire in case you want to add a 12v source in the trailer like a light, phone charger."
"Auxiliary power provides an additional option for attaching additional lighting. The 5-pin should have feeds for tailight, brake, left turn, right turn and ground. You don't have to add an auxiliary, it is a courtesy for those that want additional lighting on their trailer. Thank you and ride safe."