864Tahoe

I have a 03 Tahoe z71. I have a service 4wd message across my panel. When I first start the truck the lights on the 4wd selector switch will illuminate, but after it’s running they don’t work I can push every one and nothing happens. I unplugged the transfer case motor to see if they would light up but nothing. Any idea to why it’s saying this? I check the connections under the truck there’s 2 bolts but everything is clean and connected. Plz help

73shark

Welcome to the forum. Post over in the Tahoe section of the forum for more views as this is the welcome new members section.