Tesla Model S Side Collision Warning and Avoidance

Tesla Model S Side Collision Warning and Side Collision Avoidance. I was in the left lane of Interstate 40 west bound through New Mexico with Autopilot engaged (TACC Autosteer), passing an 18-wheeler in the right lane. The 18-wheeler driver apparently got distracted, and began drifting out of his lane to the right. You can hear his tires run over the rumble strips on the right. He overcorrected back into his lane and partly into mine. The Tesla sounded the Side Collision Warning alert, and I believe