NHTSA Complaint #11670497 — 2023 TESLA MODEL 3

While driving with the Adaptive Cruise Control enabled, on California highway 5 on Aug 28, 2023, the vehicle applied the brakes very aggressively and suddenly, shy of making a complete stop, without any object or shadow requiring it to do so - known as the "Phantom Breaking". It was so dangerous that if it was a weekend with many cars behind me, I would've been violently rear-ended and perhaps not lived to report this incident. This happened twice in two hours, to the point that I have never engaged the cruise system again. The Adaptive Cruise Control (ACC) system (which is part of the Auto Pilot system) on this vehicle is dangerous and should be avoided. I wish the vehicle had the [old fashioned] non-adaptive cruise control but it doesn't. Answering the questions: Nothing failed but the ACC clearly malfunctioned since there was no object, shadow, road animal, change in asphalt color, etc. to cause it to abruptly break. It was a clear sunny day. Any accident at such highway speed could've been deadly to multiple drivers on the road. When I informed the dealer, they "verbally" acknowledged and informed me of the term "Phantom Breaking" that they had heard of the problem being reported by others but nothing to worry about and they didn't inspect the vehicle. There we no warning lamps, messages or symptoms prior to the problem. Again, this issue happened twice within a two hour period and I have not used the ACC system again. My spouse was with me in the car in both cases and witnessed the scary situation.