This happened to me 3 days ago! I called my dealer and they said I needed to come in as it might be an "electronic issue", which was incorrect as when I got there a service tech told me this is a bug that MB is aware of. He said it's that the iPhone has so much info and the MB can't process it all. (?) Just shut down the iPhone and restart it. It worked! Good luck!This just started a few days ago. I tried using different phones, and a new wire, no luck. Any ideas short of going in to the dealer for a reset?