Several things could cause this First i agree withe the fuse being bad;
But if there is a wire loose somewhere or it is shorting out due to moisture or somthing like that would be somthing i would look at real closley too ok? and with the fuse deal if you are using the wrong size of a fuse it will cause this problem so look at this too also check the other fuses to make sure that they are all of the right fuse size too?
I hope that this has been very helpful for you
best regards michale