well it has not been hooked up in the last 9 months I have owned the boat, and it looks like it hasnt been hooked up for awhile. Could it be something off from the smart craft data wires that would feed to one of the gauges? If not, I will just eliminate it. It appears to be a 3 wire trailer harness. Maybe it went to a trailer light kit at some point. There is not a trailer light kit on it now, and all the trailer lights work.thank you for your input. Any advice is greatly appreciated.