2017 Honda Accord forward collision avoidance problems

While driving on an interstate, I started reducing my speed as I was approaching my exit. Before I could exit, my car automatically came to a complete stop. I was rear ended by a truck that was behind me. There were no vehicles or objects in front of me. 911 was called. The passenger in my car had to be transported to the hospital. My car and the truck had to be towed away. No warning lights appeared. My insurance company will be inspecting the car at the tow shop. Everyone involved safety was put at risk.

Lkas, ACC and pre-collision braking all fail intermittently. I have taken the car to two separate dealerships for diagnosis. The first advised me to replace the optical camera, the second advised me to replace the microwave radar, but neither would affirm that the replacement part would eliminate the intermittent failures. When the system fails, all associated safety features as well as cruise control are disabled for the duration of that trip.