I lost the video feed after a very minor crash. The issue was fixed by replacing the gimbal. I've seen other references to the loss of the video feed after a minor crash, wherein the fix turned out to be replacement (or adjustment) of the ribbon cable that exits the back of the gimbal and enters the front of the aircraft.
When you say "main controller" I assume you mean the radio. The loss of the video feed doesn't have anything to do with the controller.