Got a new kenwood stereo to replace the old kenwood one in my VW polo 1998. Workes fine but when I pushed the stereo into my dashboard a wire came out so I pulled it out and put it back in. It worked, but next morning my car battery was near dead, I unplugged the stereo and its fine now. I assume I used wrong wire? Does anyone have a diagram or picture of how it should be wired?