Have 17 Tahoe with same issue. I took it to my favorite local mechanic and he did some research. Bottom line is he advised me to take it to the dealership because he did not have the required software for making a diagnoses that would be acceptable too the warranty provider. He said he could call in a specialist to do the diagnosis but it would cost an extra $400-$1,000 labor which the warranty provider would not cover. This extra $$$ would not apply at the dealership since they already have the official GM software. I guess I have to believe all this because my guy spent about a day and a half pulling and researching the trouble codes, calling the warranty provider, checking out the specialist, etc., etc. and did not charge me anything!
As an aside, I had a new windshield installed recently and the Tech did spend an hour or so doing a lot of recalibrating but this message did not show up until several weeks later. Related or coincidental? Beats me?! Have not yet taken it to dealership because I do not have one nearby. Nearest is about an hour away and besides that, I don’t know which one to trust with the job! My local guy (whom I trust completely) gave me his opinion on which one but haven’t made an appointment yet. I thought about asking te windshield installer to calibrate again but that would probably be awaited of time?