I was driving on the freeway with adaptive cruise control on. out of the corner of my eye, i saw a vertical red line flash once on the dash display. suddenly the car braked and came to a complete stop. there was also a loss of power as i could not steer the car to the shoulder. there was nothing in front of me at the time. thankfully the truck behind me was able to swerve and avoid hitting my car. after stopping, i shifted the car into a lower gear and then back, and was able to drive again. i brought the car to the toyota dealer, but they could not reproduce the problem.