1991 c1500 electric problems

[ByerlyObs]

My 1991 c1500 has a thing were only sometimes does the ac heat radio etc works but it's either none works or all of it works. Has anyone else had a problem like this and know how to fix it.

 

[Deancr11]

I had a 94 that did that. I pulled all the fuses cleaned up all the contacts and such fixed 97.58284% of my problem