Just a quick response to this then I'm done. I don't want to argue.
First, a dealership cannot void your warranty. Only the manufacturer can do that. The dealer can refuse to repair your car if they so choose, but there could be consequences for them.
Second, it's not what *I* think the law says. The law is very specific and clear in this case. The burden of proof is on the manufacturer.
I don't know why so many people seem to feel that discussions are arguments. If it was so black-and-white this thread would have been done long ago. Unfortunately, it's not.
I understand what you are saying and you're not wrong per se, and I've already said that. What you're not getting is the fact that it's not so black-and-white in reality and that the way things
should work is not always the way things
do work. I, along with many other owners of modified vehicles, have had legitimate warranty work denied due to aftermarket modifications. I could have pressed the issue, gotten a lawyer, proved my case and been found correct and had the work covered, but it doesn't change the fact that I was denied warranty work due to mods and my modifications were listed in the system.
On the flip side, I've taken modified cars in for warranty work and not had issues. Again, it mostly depends on the dealership. The law can say all it wants, but arguing that is a disservice to everyone like myself that has had that door slammed shut in their face. We all know that installing a tune won't have an effect on a warranty claim if your suspension fails, but people need to be cognizant of the fact that if you tune your engine and something fails with your engine that there is a very good chance that you'll be paying out of pocket.