I have a 2003 bonneville that lost power to almost everything. With a booster hooked up the horn blows constant. I took out the fuse. The only things that have power is,,,the power driver seat, the em flashers, the key ignition light, horn that blows steady, no dings, lights, fuel pump,dome, any ideas? It is at an auction. tx

Probably a flooded car from Louisiana.

I'd start by checking the battery connections at both ends.

some kind of water build up under the seat. could be sunroof drains too