Apparently you have never been a victim of this said FEDERAL law. I have. It involved a brand new 335i coupe and an injen intake and they said I may have accessed the ECU. ENTIRE WARRANTY VOIDED! I had a team of attorneys fighting the corporation. After 30K I decided to stop and just get rid of the car hence my IS350. Of course I still feel a lot of anger over this since I have to pay attorneys every month for something so ridiculous. Of course the story is so much longer.
I would rather not air out my dirty laundry on an internet forum therefore I take a subtle approach and say what I did. You have to understand that yes it is a law and yes I have read it numerous times but who is going to enforce it? The FBI? No.
In the end I realized a few valuable things.........Car dealerships are the scum of the earth and will lie, cheat and steal to get $1 out of you. I also learned to never do anything to a car that does not come from the dealership with a full warranty unless I buy a non-warranty car and mess with that.
A car dealership can pin whatever they want on anything within reason. Mine was totally unrelated and could be proven by an expert at a high price in court. It is a very long story and I would be happy to share it with everyone but not via forum. Too much typing
I hope that clears up a little bit of confusion as to why I gave "bad" advice. Although I will take donations for my attorney's