Sosbee78

I am possibly planning on replacing the starter on a 1993 F-150 XLT 4x4 4.9L with the Mazda M5OD-R2 tranny. There seem to be 3 wires coming out of the harness coming from the battery, etc. The guy who mounted the one on it now only hooked up 2 of these, and it ran good for awhile, and now it's giving me . My question is this: Where do all 3 of these wires attach on the starter?? Does anyone have a diagram that I can easily understand?? The unattached wire is about a 1/2'' thick, black, and has a ring-shaped tip. I have NO idea where it goes. Any help is appreciated.