chevy tahoe 4x4 service light is on?

[RRSarah]

"service 4 wheel drive" indicator is on constantly. I can now no longer switch out of 2 wheel drive to 4 wheel drive. Is there something I can do besides taking to dealership to fix problem. I feel like nothing is wrong with it but it has turned off the 4 wheel capabilities. Before this occured the truck would switch to 4 wheel even though the indicator came on.

[David]

I had the same problem with my 2001 chevy silverado and it ended up being the four wheel drive switch was bad. I took it to the dealer they charged me like $300 to diagnose and replace the switch. If I could find out that the switch was bad on my own I could have replaced it my self.

[Sam]

transfer case motor is bad...sometimes it will switch over and sometimes it will not.. so change that motor and it will be ok.