Wiring for 1993 200 hp Yamaha motor

My boat is on a boat lift in a private dock. I've had to buy 2 new batteries and I have no power to starter/ gauges/ tilt and trim. I found 1 wire off when I started this and if I hook it up to a good battery the trim motor will raise the motor up and continue to run. To get it back down I must reverse polarity. I'm trying to re-wire the whole thing and I think I might have a stuck relay??? My book tells me how to check the relay but it does not tell me where the relay is. Please help. I don't understand why this wire was off in the first place. It's one of the larger gauge wires coming from the motor wiring harness.

[boats.net]

Number 10 and 11 are the trim relays in diagram. http://www.boats.net/parts/search/Ya...202/parts.html

Thanks so very much. This will help a lot.