I have a Z3c got the Sim from AT&T after the unit was online I was able to see cellular was active.  I unplugged my network and the unit worked great. Powered off the unit and restarted with no Ethernet connected and it will not connect to the Cell network.  When it powers on does it always have to be on a wired network ?   Also I was told to add "broadband" to my apn field  did anyone else do that ?  ... View more