All the sudden my 4WD stopped working. I'm sure it still works but none of the lights come on when I start the truck. Not even the 2WD light comes on. No sounds when I push the button even when its in nuetral. Don't even know where to start looking! Please help!

Start by checking the fuses in the fuse panel by the driver's door. Check them with a test light, rather than just looking at them. Then you need to see if 12v is coming into the 4x4 switch on the dash.

What year vehicle, how many miles, and is it 3 or 4 button 4x4 switch?

2000 sonoma 198889 miles and a 3 button set on the dash. I checked all the fuses and they all check out and there is 12V to the dash.

If the 4x4 switch has current going to it, then it should light up unless it doesn't have a ground or it's bad. When you flip the 4x4 switch is there 12V coming out of the switch?