I've been told by my BMW dealer that If I hardwire connect my iPhone to X6M's USB input that I also connect to the car's internal cell phone antennae that's used by the car's BMW Assist system (like OnStar, where you push the button and a live person says (Hi, how can I help you?). They say that gives you a stronger, more stable cell signal/connection.

Anyone know yet if this is true of the Porsche system? Does the car have an internal antennae that you connect to when you hardwire your phone to the car's USB port instead of connecting by Bluetooth?

 

I believe that the external antenna is brought into play if you have the Porsche factory telephone or the telephone module (which allows you to switch to the SIM access profile). Connecting to the usb interface with your phone only engages the audio and log book functions of the pcm.