NHTSA Complaint #11440469 — 2018 TESLA MODEL 3

I was driving on interstate, using adaptive speed control but not autopilot. Middle lane. Car suddenly applied brakes. A car was ahead of me but not very close, there was no reason to apply brakes. Slowed down from 65 to 45 very fast, (seatbelt tightened) before I resumed acceleration myself. Lucky I wasn’t rear ended because traffic is usually heavy in that area. I had one passenger who was as surprised as I was. Yes, the car can be inspected. Not reported to Tesla. No warning messages, including didn’t make the loud sound Tesla makes with normal city driving if a car ahead is turning right and I start to accelerate before it has completely left the lane I am in. Tesla cameras are also not seeing cars traveling in my driver side blind spot. They used to show up on the screen but haven’t for months. Tesla cameras also do not see low flat bed trailers (such as empty car carriers) pulled by pickup trucks, common in Ohio. Screen shows the truck but does not show the trailer. I don’t use autopilot because of the blind spot issue, now I’m afraid to use cruise control too.