Will not start and electrical Issues when wet

Back in the rainy season, my SUV's windshield wipers would not work if the headlights were on. The radio would not work if the gear was in drive. One time I felt a drop of water fall on my foot as I was driving and my foot was on the brake petal. Also the truck would not even start until I would push the reset button under my dash and turned the key at the same time. I also noticed that my doors sometimes would lock themselves if the truck was on and not in gear and when I would unlock the doors not all doors would unlock all the time. Usually one random door would remain locked. Since I have noticed this happens after it rains and my front end gets wet, I have been careful to park under my carport. I did not know it was going to rain over night so I left my truck out and it was sprinkling all night on my truck and this morning it kept trying to start itself with no one anywhere near my truck. When I started it, it still tried to start while it was on. I just unplugged the battery and decided to let it dry out under the carport. Can somebody please help?