> I would expect a judge to determine that someone has exceeded their authorized access to a computer and, as such, their behavior is in violation of the CFAA.

How would that work if the computer is owned by the supposed infringer? Has there ever been a judge who ruled that the CFAA applies to computers the defendant owns?

I guess I'll start my second comment related to legal matters by stating that I am not a lawyer. :)

I don't know about the CFAA, specifically, but to my knowledge DMCA 1201 has been used to stop independent car repair shops from accessing the diagnostics computer by encrypting it and saving the encryption key in plain text right alongside the encrypted data. Accessing that encryption key to decrypt the data in a computer that's ostensibly now owned by the person who's trying to authorize the decryption has (at least seemingly) been found to be in violation of the DMCA. I have no idea if that's ever actually been challenged (though I would assume it has).

In that legal environment, the aforementioned potential CFAA ruling seems likely.

I think its pretty unlikely that car companies ever go after customers who modify their own vehicles and test that legal theory directly. Making it so that enabling the features requires reflashing firmware and leaves a trace so that they can deny warranty claims seems much more like the kind of thing they would do.

I guess considering this, they'd be more likely to go the DMCA route in regards to, e.g. a discussion forum that has many posts detailing how to bypass feature authentication. It's a good point that they probably would not target individual consumers.

That’s not how car warranty works. In the US Magnuson-Moss protects you from this.

You can literally engine swap your car and still make hassle-free warranty claims on your suspension.