I recently bought a used A-1, which has a problem. When you try to press down the shutter button you get EEEE EE display in the view finder. I tried fixing it the way it says in the manual with the stopped-down lever but it didn't work. I am still getting the error message and I can't get it to take a picture. I am doing this without film in the camera. Any one know what else could be causing this and how to fix it?