Aftermarket parts in new Civic with Warranty

The simplest answer is that areas affected by the aftermarket system will be rejected. In this case, if the door locks don't work afterward or if something is broken in the process, the dealer won't ask Honda to pay for it; they will expect you to take it to the installer. However, if your engine starts burning oil or the tranny acts up the aftermarket work won't be a consideration (unless the installers got really wild and crazy!)

Mike

If anything goes wrong which is related to the installation then it absolutely will not be covered by warranty. Other things which have nothing to do with your installation will still be covered.

There are gray areas, like a suddenly failed battery. Honda might claim that this is being caused by extra current draw for the aftermarket accessories.

Personally I wouldn't do it.

John