To clear codes, you have to navigate through some menus and specifically tell it to clear codes.

As far as that other thing: sending commands- same thing - you gotta navigate through some menus and put some effort in. (I'm not sure why you'd wanna do that anyway - will be interesting to hear what DesurtRat finds...)

Neither of those could really be done by accident.
Other than that, all it's functions are just READING information, so I don't see how it could do anything detrimental.