In my case , once that 4x4 service display comes up , it will not go into 4 wheel drive . I could shut the truck off , key out , open and close door , then turn the 4x4 switch on , and then start the truck . It would go into 4x4 . I would only do this in an emergency. Eventually , this would not work . My total Bill was about $1000. Fortunately I had an extended warranty .Yikes! Hope all goes well. Getting snow tonight and driving about 60 miles on the Interstate in the morning. I plan on running in auto just in case. See what happens.