Supposedly, no modification can cause a complete void of the warranty. If there's an issue and it's apparent that a modification that you made was the cause of the issue, they can deny that specific repair.
They have to fix a faulty window switch regardless of whether you have a supercharger. A blown motor is a big expense, and they'll try to blame it on any mod, no matter how minor, if they can.
Supposedly, no modification can cause a complete void of the warranty. If there's an issue and it's apparent that a modification that you made was the cause of the issue, they can deny that specific repair.
They have to fix a faulty window switch regardless of whether you have a supercharger. A blown motor is a big expense, and they'll try to blame it on any mod, no matter how minor, if they can.
They won't void your warranty even if you have a supercharger necessarily, they may put you on a watchlist or such.
Yes they can deny service on a window motor, they can say that the blower made teh alternator go crazy, causing a surge, thereby blowing your window motor. ETC.
They can say that because you changed wheels that weigh more, it put higher stress on the axle which reciprocated onto the engine etc.
There is the "pro consumer" part of the Act which was intended to allow someone to have normal maintenance done on their car, at a place other than a dealer, without voiding their warranty. Before this Act, simply having your oil changed other than by your dealer, many times, would void your warranty. This act changed that unreasonable restriction and you can now have maintenance done at any qualified service place. This is also the part of the Act many aftermarket parts places like to quote to support their claims of not voiding your warranty.
There is also the "pro manufacturer" part of the Act. This allows the manufacturer to completely void the warranty if there is any evidence of abuse. Having performance mods on ones vehicle can be considered evidence of abuse. The legal theory successfully being used is that if you have them, you must be good making use of them. This is also the part of the Act many aftermarket parts places like to forget about when mentioning the possible affect on your warranty.
Of course, a lot of this all comes down to the guy in the service department. He can choose to ignore your mods, or he can choose to make a big deal about them.
This was the same for me when I started modding my Lightning - I go by the motto, "You gotta pay to play." I put in a built tranny on my truck, $3800 out of pocket, but that's what happens when you add power like that.
I know that if my car blows the motor it's probably gonna be on my nickel, which is something I accepted before putting the blower on. I certainly don't expect Ford to pay for it.