That's interesting. I'll have to contact Pioneer to confirm.
The reason I was curious is that I've test driven a lot of cars recently. Surprisingly, very few have an adequate place to stow a smartphone! To use CarPlay, you have to connect with a USB cord. The place where you rest the phone would normally compromise the phone's GPS performance. Yet Apple Maps worked as expected.
Well, if the car doesn't have the receiver for GPS, it will use the Phone's GPS. So it's mostly seamless unless the head unit has bugs and happens to pass the bad data onto the iPhone. And I'm honestly surprised how good the phone GPS accuracy has gotten lately. The difference between the iPhone 4 and 7 has been obvious to me. I don't miss having the GPS antenna with the Sony AX100. The iPhone 7 I use has no problems getting a lock quickly enough while it sits in a cup holder.