I have a 1999 Chevy Blazer LT with the 4.3 votec. I am havving issues with my 4 wheel drive. I have 4 buttons, 4 auto 2 high 4hi and 4 low. Now im pretty sure I haver to replace the switch on on itcuz some times the lights show up and some timesw it does, and I noticed when I took it out one of the wires kinda look chewed up so im going to replace the wire and switch just to be safe. But the real issue is I always drive with 4 auto and it works great, but when I put it into 4 hi or 4 low it does engage at all. The light will show thaqt 4 hi is ingaged but I only have 2 wheel drive working. But 4 auto works. Im very confused on what is going on and would really like to figure this out. Any suggestions?