4 Wheel Drive/SUVs: 2002 suburban 4wd, 4wd service, fuse box

Question
Service 4wd msg came on. It doesnt get ued that often. I put it in 4wd hi now it go back to 2wd. The dealer replaced the tccm when I bought it a year ago. I hear relays clicking in the dash and a souond coming from the front end. It sounds like its trying to disengage but won't. I have not check oil level or fuses yet.

Answer
Vince, you are not the only one to have this problem , alot of the times this is caused by a bad transfercase motor . It would just have to be checked out in a shop before you would know for sure, about the only fuse will be under the hood in the fuse box and I think it is labled something like ATC .... If i remember right , thanks alot , Adam