My 4x4 only seems to work when the weather is really wet, or frozen cold, other than that no lights show up on the switch. I have replaced the switch, the actuator, tccm, and the pigtail that goes to the actuator, also cleaned the grounds below the drivers seat on the frame. Are there any other spots on the wiring I should check?

 

Just a guess but the water or ice might actually be what's causing this. I'd get some Permatex Dialectical grease, clean all your connection up then add the dielectric grease to the inside of the connectors. Might be a good idea to heat them up first and get any moisture out, A portable hair drier works great for that, and also to keep the dielectric grease warm.,Not only will the grease keep water out but you won't have any corrosion issues. And it's cheap!