Article I Met White Label Cortana in a BMW


"Seattle is a wonderful town," it responded. "I'm just glad I'm equipped with rain sensors." In this case, it referenced sensors on board. But in theory it could also know what kind of interior it has or other available features.
OF COURSE it can know everything about the car... it just needs the right interfaces, and being told about it (at this stage of the AI game) what it can do with it (and how it can do it)... it isn't like it's truly self-aware and can determine all that on its own... plug-n-play style.

It also has the ability to be hacked, data stolen/changed, etc. If she has too much control of the car, it could put someone's life in jeopardy, especially if there is no way to shut her down.