Stereos are susceptible. A Pioneer head unit glitched out after a good rain shower. It was brand new and Pioneer told me they wouldn't warranty it. The Best Buy rep who assured me it could handle a little weather was no help. So, now I have a marine head unit designed for a boat. My sound bar, rear wedges and front dash speakers have endured a multitude of rain showers with no apparent ill effects.
There is a rubber shroud under the steering column plastic cover protecting all the wiring. Good luck finding that if you have to replace it. I tore mine when changing the blinker switch and the dealer says the part doesn't exist. I now have a piece of inflatable raft vinyl in its place which works well enough for the time being.