Very thorough interview and the best interview experience I have had.
You probably should not even apply if you are not passionate about working for Tesla.
Phone interview: for personality, interest in the company, and basic skills.
Timed Engineering Exam: on basic skills knowledge applicable to the position
In person interview: giving a presentation to a panel and a series of one-on-one interviews
This is a great interview process for determining, aptitude, fit with company culture, ability to summarize & present information clearly, and for determining a candidates actual knowledge base.
Be prepared to talk about any and all projects you have worked on, what your role was, what you personally accomplished, and what the end result was.