I started up my tahoe after lunch and it was snowing. I looked at the mirror to see the temperature and it said 32deg then switched and said ICE, then toggled back and forth a few times and stayed on 32. Has anybody seen this before? Is it just a warning for possible icy conditions, or is there more to it? Strangely enough during my trip to michigan which was mostly well below freezing, I never saw this message.