tech1955

I had this problem and youtube video showed a cable behind the glove box , I believe it was a blue connector from a computer to the radio . This person on youtube had a 2015 Denali. Unplugging and reconnection the cable fixed his situation. I had the same problem with the screen going crazy. This didn't fix may situation but the cable had to connect to the radio. I pulled the radio and unplugged the blue connector , looks like a phone charging cable . Problem solved and it has been a few weeks no problem. Hopes this helps somone. Good luck.