I repair these machines for a living all over the pittsburgh area. Are you CERTAIN all interlocks are good?
The best way to confirm this is bypassing all of them with a jumper wire. They include the feed tray switch, the clear plastic cover switch, and the often ignored 2 switches, on the rolls of film. If you have quetions feel free to call me, telephone tech help is always free:)
bob haller service and sales 412 366 4906, January 2015