STOP USING YOUR IPOD CHARGERS AND IPOD INTERFACES
So how do you know if your interface that you are using in your car is putting out 5 or 10 Volts? you'll have to call the manufacturer to find out. But if you plug it in and its set up for previous generation Ipods, it will damage your phone eventually...it surely might work, and charge your iphone, but it cannot handle that 10 Volts for too long, and it will not be covered.
BE CAREFUL.