Daughter has 2012 Edge with Microsoft Sync.  Sometimes when I start the car, everything works great AV/Heater, sometimes system will NOT come on at all.  She hits a bunch of buttons and sometimes it will come on, but again, sometimes it does not.  Sometimes when she does nothing, it will all of a sudden come on.  While driving and it's on, it will NOT just turn off.  I'm ruling out ground short b/c of this.  I have asked her to do the Power on/Defrost button, but she says it's hard because it's the defrost button is sensitive.  I guess once she comes home for Christmas break I'll try the button thing, but is there a way to test the Blower Motor Resistor (does it sound like maybe could be this)?  Any help will be appreciated.