GM Repair Problems? Ask GM Repair Expert Now.
Hi, I am Mike, welcome. I'm reviewing your question.
Do you have a scan tool?
When you press any other position on the transfer case switch other than the one it's tuck in now, 4 high, does the switch light flash indicating that the transfer case module has received the signal?
As you can see just about any troubleshooting procedure that I have starts out with the use of a scan tool.