Originally Posted by Robey5
My *guess* is that you are not getting power to the rear camera - leading you to get the black screen when shifting into reverse.
My guess is it's not a power issue so much as a camera sensor failure. Without a powered source attached, most video monitors will display blue, not black. The black screen usually occurs when power and a video signal are received, but the sensor on the camera itself isn't providing an image.
However, your suggestion of checking the fuse would be an easy way to tell. If you pull the fuse, it ought to go to blue if what I stated is indeed the case for the dash unit. If that happens, it's the camera, not the power supply.
On the other hand, if the system doesn't have a "no signal to blue screen" function, then you'll be able to check the fuse at that point to see if it's bad or not.
The next step is checking the camera itself. Mine often fogs over in the rain and I really wonder how weather resistant they really are.