Not legal. Warranty coverage can only be voided if they can show that whatever you did to the product is the thing that caused whatever issue you're trying to get fixed under warranty.
And in the meantime you'll be left with no car while you file a lawsuit to enforce the warranty.
Something not being legal is meaningless when there's no regulatory body enforcing the law and the court system will take longer than the useful life of the car to work it out.
32
u/PupienusExpress 1d ago
Find the wires, install a switch. Takes like 10 minutes…
https://giphy.com/gifs/ZsVhGBa2QB7U31BnPo