While it is possible that you have a module or input problem, I need some more info. Is the camera on the Rear View Mirror, or do you have the Navagation Radio with the camera display there? If it is on the mirror, then lift the mirror up and check that the electrical connector is seated all the way (we usually reccommend unplugging it first and checking for loose terminals, then plugging it back in firmly). If it is on the Nav Radio, there is a software programming update for this concern. Have it programmed before looking any further.
Next: Are there any aftermarket electronics or modifications installed? There have been some real issues with some of them. Let me know.