My automatic transfer case doesn't work

2002 trailblazer. The orange light indicating 2HI, A4WD, 4HI and 4LO isn't on. It doesn't go into 4WD. There is no light on the dash indicating i need to service the 4WD. I haven't used the 4WD for about 8 months. The light was working fine about 2 months ago. Is it a fuse? or what is going on? I am due for a regular tuneup, could this be the problem?

There have been issues with the dash switch , the encoder motor and some software updates with the encoder, I repalced my dash switch for similar symptoms but have it checked out.

I had the same problem on my 02 LT and I found out that you can just disconnect your battery for about 3-4 minutes then reconnect. It resets it without loosing your radio pre-settings. That is what worked for me.