I am not sure what the tipm has to do with the rear camera and the BCM flash, but I've heard stranger things.
My *guess* is that you are not getting power to the rear camera - leading you to get the black screen when shifting into reverse.
First - I would inspect the fuse link that the camera is on. There may be an intermittent connection there that works itself loose from time to time; and now your fuse may have worked itself all the way from the secure connection it once had. Speculating, but that is my first guess...
Good luck!
My *guess* is that you are not getting power to the rear camera - leading you to get the black screen when shifting into reverse.
First - I would inspect the fuse link that the camera is on. There may be an intermittent connection there that works itself loose from time to time; and now your fuse may have worked itself all the way from the secure connection it once had. Speculating, but that is my first guess...
Good luck!