Chinese rubbish so I should have expected this. Not very well made and absolutely terrible instructions badly translated from the Chinese. Came with a broken CD. Vendor didn't replace just sent me downloadable instructions on a PDF which I can't get to work. Don't waste your money.
I don't recommend this at all. Reads like the author hasn't owned or worked on a Benz. You get more information from forums or watching a YouTube video than this rubbish. Save your money. Also - avoid "Mercedes-Benz E-Class Owners Bible" - that one is a joke.