New guy here, so excuse me if it seems I'm jumping in. Highly unlikely the wire for a brake controller is pre-existing in anything older than a 2000 model - my experience is that you'll have to run a wire down the chassis to connect the controller to the connector. Just bought the 85 Coachmen in my avi, waiting on the weather to cooperate so I can get MY trailer tow wiring done so we can safely tow our race car this spring......