NHTSA Complaint #11441021 — 2021 GMC ACADIA

My 2021 Acadia just stooped working as COMPLETLY SHUT OFF. I had no power to contact OnStar or more importantly to put my 4 ways(Hazard lights) on to signal or warn other motorists that there is a problem ahead. I could not push the vehicle as it is locked in gear because of the termination of power. I have had this exact problem happen 3 times leaving me and my family stranded on a busy road with nothing working. On each occasion I have removed my family from the vehicle in fear of being rear-ended! This would not only cause an accident with harm or fatality to my family, but has put that same risk to other motorists on the road. When I have had the vehicle in the dealership (Champion Buick/GMC of Brighton) in which it needs to be towed, they have not been able to find or confirm this issue. The dealership has had the vehicle for multiple weeks with help and assistance of GM with also no resolution. This is a very intermittent issue and when it happens it is an extremely dangerous situation. The vehicle gives no warning except for a total shut down.