I put in a manual fan switch. The switch was one of those that lights up when turned on and when i got it wired it worked but after about a minute smoke just started billowing out and the terminals melted out of the plastic. The fuse is the same rating as the switch, but it didn't blow. Could I have by passed the fuse somehow?

 

Either the fuse or the switch may be defective, the fuse should be a slightly lower rating than the switch like 15 amp switch, 10 amp fuse, just to protect the switch.