Yeah, what wastedonanime said. But my service guy told me that anytime you touch the electrical system you risk voiding it. If you put in an aftermarket stereo and something goes wrong with your electrical system 2 years later, They could legally blame it on your stereo addition and void the entire system...
They have to prove that the aftermarket item caused or contributed to the failure of the Honda item. In a past life I was a car stereo installer and dealt with this all the time. The rub is if you don't really know how the electrical system works, and can prove that what you added didn't cause the issue, then you're pooched. I have been in many battles with dealers over the years, fortunately, I know enough to make them consider it was there failure (if in fact if was).
for example. My battery won't hold a charge. I have all kinds of aftermarket electronics on my e radio, gps, blue tooth kit, and the list goes on. When I take the car in they will say its my fault. when I do a current draw test in front of the service adviser and prove that there is no draw on the car when the alternator is off, then they will replace the battery
hope that helps
Mitch