There's not really one thing all those systems have in common, other
than perhaps the ground. Check all the grounds.
If you can't find it, you could try to bridge the ground by using a
booster cable: using only the negative side, attach one side to the
negative post and use the other negative terminal to experimentally
attach it to things that should be grounded (like frames, brackets,
etc). Once you find it starts working, you have a clue as to what area
to look into.
It could be that a ground connection in the dash someplace is not
making good contact.

Remco