So the first two lights of the button module on the dash went out. Then the message read "Service 4WD", then all the lights went out. I then bought a new button module, because I know these tend to go bad a-lot.

I swapped the old out for the new, and the buttons all lit up. But, the message still read "Service 4WD" so then I was told that you have to unhook the battery for 15-30 minutes, so I did. Hooked the battery back up message was gone then I realized that the indicator light was not lighting up. I drove around the block to see if although the light wasn't working, the 4WD was. The 4WD was not working.

Any suggestions anyone?

2002 Chevrolet Silverado 1500 5.3

 

Could be the soleniod, those too with the switch are common issues. My 2000 suburban had that issue, it turned out to be the switch.

 

Thanks. It turned out to be the ATC fuse. After searching the Internet for someone with the same problem I found a list of fuses to be checked, and that one was bad, put a new one in and BAM all better!