Forward FishFinder Interference

[mtstringer]

Hello all, I have a 1995 372V and when I bought the boat it came with a forward Humminbird fishfinder on the trolling motor. The person I bought the boat from told me that whenever he used the trolling motor the finder would pick up interference but clear as soon as you take your foot off. And it does. I had heard that was caused by powering the finder from the same circut as the trolling motor. I took a look at the finders wiring and it is wired to a terminal board in the bow panel not the trolling motor wiriring. I also found two red and black wirers that went to nothing. I thought that maybe the red was a hot wire but there is nothing there. Anyone have any idea's or schematics for the bow wiring they could send me.
Thanks
MT