Fuse block brown out?

[Subzilla]

On the '86 Blazer, a few of my add-on accessories lost power. They are plugged into constant power ports on the fuse block (but I do have in-line fuses for them). Checking with the volt meter, there is no power to these ports. Everything else works EXCEPT for the overhead dome light and rear dome light BUT the floor light does work?!?! I'm not sure if these problems are connected or if the dome lights are just a separate issue with uncanny timing.

Why would just a quadrant of the fuse block quit working? Is the whole fuse block on a breaker or fusible link somewhere? I've always wondered what protects the fuse block from burning up.:confused:

[crashz]

I've seen the connections at the firewall corrode significantly enough to cause major electrical problems. I've seen an 87 gasser that lost all functions in the matter of a week or so. We pulled the block connection at the firewall and all the pin connections crumbled. It was a seasonal plow truck though, that rarely saw a carwash...

[Subzilla]

KISS.......a simple blown fuse replacement fixed the problem. The dome light/horn fuse port also supplies power to the other 4 empty ports I had my accessories plugged into. I assumed these ports received power directly from the battery so I had in-line fuses for my accessories.

Anyway, problem fixed. I'm still baffled as to why the overhead dome lights are on a separate circuit from the floor light.