The wire is screwed into a metal plate ?

If the fuse is dead with or without the key on, how do you know it is not blown ?

the picture you took, that is what I was talking about, and if it is on the wrong side of the fuse ( and wired to the truck's ground ) that would cause it to blow.

You cannot have that connected to a ground, that is power ( either going to the fuse, or from the device side of the fuse if installed incorrectly ).