I have a 2008 Suburban LTZ with 5.3. It has tons of electrical problems. Driver window won’t move. Replaced switch and tested motor. Both are good. Driver power seat doesn’t work. Tested switch and motors no problem. Passenger seat control only some functions work. Stabilitrac comes and goes. Remote start begins to crank then quits. Locks will randomly lock/unlock.

Any ideas where to check? I have checked connections and grounds where I can.