kymarto wrote:
I'd take the lens off, put the camera on B and visually inspect the sensor, first thing. Also fire the shutter at slow speeds without lens and see if the shutter is doing anything funny. In any case, unless there is something physically blocking the sensor that you can remove, this is definitely an issue that needs the camera to go to a competent repair person. And I don't think it's going to be cheap if it is senor or shutter related.
I did all that and everything appears to be working correctly. but I am not a camera repair person, so I am sure there is something going on that I can't see.