I put a trailer brake controller on my 2015 Vegas several years ago. The stripped van chassis ( at least in 2015) had neither the brake wire or the power wire hooked up - there is no little plug under the dash like most other cars, trucks, and vans these days. The brake and power wire exists in some of the wiring harness , but is not connected at either end. At the hitch, you need to find the wires and connect to the 7 wire connector. At the front end, both wires terminate in the the wiring harness under the drivers seat ( harness along the frame ) , and you need to wire everything else to the controller.
If you have not done this before , might consider having a trailer place do it ( or the dealer if you are very rich...)
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