4 lights

[borkfarm]

I have about 1000 miles on my 2500 Denali, and about 1 mile from home 4 square lights appeared on the windshield as the seat vibrated.  There is no heads up display onthe Denali, What was that???

[CmackR56]

I had a 2018 Yukon XL with no HUD. The front collision warning flashes on the windshield. Evidently you were too close, the next thing it would have done would have been to apply the brakes. Rather unsettling.

[borkfarm]

Really strange, since I was the only vehicle I could see for miles out here in rural America