the fan switch when on it does not go i've tryed changing the switch but still no go what could be wrong?

check the fuses or behind the glovebox on the heater box theres a small panel screwed in there (dont know what its called )its got a bunch of wires coiled up on the inside of the panel on the outside theres a plug with three or four wires .sorry about the crappy discription its off the top of my head.