NHTSA Complaint #11508305 — 2021 TESLA MODEL Y

On February 19, 2023, I was driving my 2021 Tesla Model Y on I-5 from LA to Sacramento on a clear afternoon. I was using adaptive cruise control (ACC) set at 78 mph, but not using auto-pilot, in the fast lane with a car following me. My car suddenly braked aggressively without anything in the roadway ahead of me. I then applied the foot brake and veered off onto the gravel left shoulder to avoid having the car behind me hit me. I saw in the rear-view mirror the following car swerve to the right to get around me, entering the slow lane. I believe that when I stepped on the brake, the ACC turned off and the car's automatic braking ceased. I then got back into the fast lane as there were no other cars approaching and resumed my drive. I didn't notice the speed my car had decreased to during the incident before I resumed speed, but I guess it may have been about 40 mph. Phantom braking happened one other time on I-5 on my way to LA from Sacramento two days previously (Feb. 17) also while in ACC, but there were no other cars around me and the automatic braking stopped when I tapped the brakes and I resumed my speed. In the year and a half we have owned the car, we have experienced approximately 10 instances of phantom braking, but fortunately, no accidents.