Q: 4x4 won't engage and push button switch lights up intermittently.

Truck won't go into 4hi. 4lo or nuetruel by using push button selector switch. Replaced switch did not help, resoldered cold joints inside switch did nothing either. Checked all fuses. Cleaned grounds on frame below driver seat. Disconnected batteries and pulled 4wd, transfercase and power train fuses for 1 hour. The lights on switch will show I'm in 4lo or N while going 80mph, and I know it's not right. Service 4x4 message on dic and some times the lights on dash will blink and gauges flutter with blinking lights with key on, once started no problem from lights or gauges. With all the crazy problems I'm leaning towards elec problem rather than actuator or encoder motor although I have not tested them. I did try installing aftermarket head unit before I knew about the class 2 serial data wire. I now got factory radio hooked back up and is working fine but could I have fried something?