My 2016 Colorado Z71 has been shifting from 2wd into 4H without the button on the dash shifting. Button in 2wd truck in 4wd.
Whole Story:
At my last service the tech said I was due for trans & diff service. A while later I noted a “service 4wd” message on dash, I ASSUMED it was the service my tech had mentioned (oops). I had them serviced 300 miles later I saw a message on the dash that said something about 4wd but it disappeared before I could read it all. (It was more than service 4wd). Today my truck was in 2wd when I did my UTurn when I left home, steered normally. When I reached my destination (6 miles) I could not get the truck to turn into the parking spot. Which I later recognized as the typical steering of my truck in 4wd, checked the 4wd switch and it was in 2wd. To test I put it in neutral and switched to 4wd, I got no shift in progress notice on the dash. Then I switched it back to 2wd, I did receive the switch in progress.
1. How can the truck be in 4wd when the switch is in 2wd?
2. How could it switch into 4wd while driving?
This seems electrical to me. What could be wrong?