If you have FordPass Connect/SYNC Connect, then you can have Wifi in your vehicle via AT&T. No other carrier will work with the built-in modem. We travel a lot & use Verizon for our cellphones, however have the Conncected Car service in our Expedition and Ford Transit. Sometimes (not too often) we will have wifi service when there is no Verizon signal.I am totally lost here. What feature are you talking about that requires ATT?