Being the most inept mechanic in the known world, I was screwing around on my '98 California EV. My V11 Sport and Ducati perhaps in the shop from now through eternity. So the taillights and turn signals intermittently fail. I've diagnosed (Lord help me) the problem to the fuse. It's just doesn't make good contact. So occasionally I have to reset or wiggle it, clean it with contact cleaner.
Yesterday I went through the same drill. So today I decided to clean all the fuses and relays with DeOxit and contact cleaner. I replaced the fuses and relays a few years ago. They're all identical (15A). All cleaned up and randomly put them to their respective slots. And I never got the taillight/turn signals to ever work. (Brake light is fine). I play with all of them, reclean, move them around for perhaps an hour. Nothing.
As last ditch effort I pull an old fuse, different brand, perhaps one I pulled out in the first place. And it works. Like magic. Not content, I find another one. An old fuse that is corroded and worn. Works fine.
OK, What the heck? Someone tell me.