New to me truck trying to fix some of the issues. 96 K1500. The driver side power window, power lock, and mirror adjuster are all not working. The switch that moves the passenger side window is working tho. Is there a common ground that those all share? A switch? Fuse? I would be surprised if the regulator power lock motor and the mirror motor all are bad vs something in common causing them all to not work...!? Any help with direction or ways to test each component or look for ground problem. I will take the door panel off and start checking things with some help hopefully, TIA