Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Hello, my name is Bobby. Thank you for the question. When you get the flashing light do you get any noise also?
That is a common issue, but it may be a transfer case issue. I would start by draining the fluid from the case and inspecting it. This will allow you to check the fluid for metal and other signs of wear. If the fluid is fine then we can run through some electrical diagnostics.
Then it is more than likely electrical. Do you have a scan tool to read the codes in this system?
Can you feel the encoder moving when you try shifting the*****
Then it is more than likely the transfer case control module keeping it from disengaging. It may be because it is getting a bad input or it is simply failing.
It is very hard to diagnose these unless you have a breakout box to do so. You can try a used one as it may work if it is in good shape.