tesla's system is lane following which has a radar that knows when the cars in front of you slow down or speed up. that's pretty much it. it's not an autonomous car in general. mine is very reliable for cruise control adjustment, good but not awesome for lane detection (falls down in bad rain for example, works well in clear weather). it tells you this, via display, it knows if its working. I can't understand these fools who thinks its some super advanced system. it really does little more than follow lanes and adjust speed based on detection of cars in front.