New issue yesterday on my 2001 LT with 4 button switch. Won't go directly from 4WD hi to 2WD hi. 2wd button flashes for some time and then 4WD hi lights back up. If I put it in 4WD auto before switching back to 2WD HI, all seems fine and 2WD Hi button will stay lit. Any comments or advice before I get into the diagnosis? At one point the service light came on and then went back out on its own while I was jacking around with the buttons. Didn't come on any more. Can't remember what I was doing at that moment. Up to this point 4WD on/off and auto 4WD has been working flawlessly. This was after about 40 miles of driving, much longer than I have typically been driving, and it was much warmer yesterday as well.

 

I had somewhat same issues...Cleaned connections on TCCM and applied dielec tric grease. Has been working like champ ever since...


Much thanx to the guru's here!!

 

Hey thanks.

 

Had the same problem for about a year, Had to leave the switch hanging out of the dash and wiggle the wires to get i to go into auto4x4...

Finally took the dash switch out, [4 button switch] and re soldered the input connections...looked at it numerous times, under a magnifier, couldn't see any cracks...Works like brand new..

If your 4x4 switch is acting up, try this first..
351436

 

OK - so the consensus of two people is loose connections for the 4x4 control, either at the dash control or down below. Makes sense. Easy to manipulate the wires and see if anything changes. In my case it has been a consistent problem since it started last weekend. Lake effect snow coming tonight, so I'm going to leave it alone for right now. Don't want to do anything that might affect going into 4x4, even though that has not been a problem thus far. Thanks.