Warning Light On problems of the 2014 Toyota Avalon

While traveling in the left lane at highway speed with no other vehicles in the lane in front of us for at least 100-150 feet, the collision avoidance system randomly engaged. This caused the vehicle to brake very hard, which caused us to decelerate rapidly (losing 20-30 mph in a short distance). The warning beeps that are normally associated with rapidly approaching another vehicle/barrier in front of the vehicle also were sounding, and a warning light came on the instrument panel. In addition, the seatbelts on both front seat occupants locked and drew us forcefully down and backwards into the seats. This last approximately 2 seconds, at which time the beeping stopped, the emergency braking stopped and the seatbelts loosened. The driver was able to maintain steering input throughout and the vehicle continued driving normally afterward. At no time during this event was another vehicle, animal or barrier in front of the vehicle and there were no near-collisions that would or should have caused the system to engage.