The matter of a side collision system has been raised in this thread.
The other day I was driving in very heavy rain on the interstate. At one point, when I was being passed by a faster car in the lane left of mine, there was a buzz or warning tone and the steering wheel tried to jerk right in my hands, which was not too hard to resist. I assumed the car passing me raised a rooster tail of water that must have gotten pretty close to mine, triggering some kind of side collision prevention system. If so, it was a misfire that they should try to program not to happen.
I think it happened when I had AP off. I did try AP on that drive because the display showed it was reading the lane lines despite the heavy rain and bad conditions; however I kept my hands full on the wheel because of those conditions. Although I think the misfire occurred during the time I had AP off, I am embarrassed to say I can't be 100% sure thinking back on it now: there's a small chance happened was while it was on.