Whatever is the equivalent of an ignition switch in a Diesel

I apologize if my response was confusing. I didn't mean a bus fuse, I meant a bus strip. I hope I'm using the right terms. I don't know what's inside the fuse box (besides fuses) so I don't know how fuses 5, 6, 7 and 8 link up to the wire from the key switch. I'm guessing there's a bus strip. I've never heard of a bus strip breaking but maybe it's grounding on something.

Sixto
95 S420
87 300SDL