Sounds to be electrical, but one thing on your system that could cause all that and throw no codes is a bad computer. When it heats up it goes nuts. Its not definate I have seen 2 computers act crazy due to overheat. The only symtom that was the same between them was that neither ever threw a code.
Usually in shops when a computer is bad you will see a long list of things that were replaced and at the end of the list is the comp. Best way to check the harnesses is start the jeep let it warm up, and wiggle the harnesses or the suspected wireing to try to duplicate the problem in you driveway.
There is another way with a spray bottle filled with water but that one tends to shock anyone in the area.