You getting a 4wd icon on the speedo? There are two wires coming out of the front diff. Follow the brown one and hook a jumper wire to it and ground the jumper wire to the frame somewhere. There icon might still not work, but the 4wd should. The switch send a signal to the speedo and then to the diff. If the jumper trick works, you prob have a bad speedo. Same thing happened to my 06 700 efi.
700 Sportsman Snorkeled Out 2" lift 28" Mudlites Warn 3000 Tunes, Flashers and a few other goodies to make it go faster and go deeper