AVIC-Z130BT Backup Camera has No Picture

Starting off, I will admit I have very limited knowledge of stereos but have already searched this issue to come up empty handed. My dad purchased a 370Z with a Pioneer avic-z130bt and a backup camera installed; everything worked absolutely fine (I drove the car several times myself).  Without knowing 100% what he did, he synced his Iphone through the Bluetooth connection (which works fine) and set some radio presets.  He is adamant that is all he did, he did not wander into any settings.  Now when the car is put into reverse, the screen changes to black with the message "Images may be reversed" at the top; there is no video like before.  I checked that the camera is set to on and the polarity to battery (which he says he had never touched).  Any ideas on what could be causing this?