We have a Canon ImageRunner 8500 and we get this

In this case the finisher motor or motor sensor does not work properly. AS SM Main cause - The tray B lift motor (M12) is faulty. The tray B idle rotation sensor (PI18) is faulty. The tray B lower limit sensor (PI24) is faulty. The tray B paper sensor (PI17) is faulty. Main cause The tray B lift motor (M12) is faulty. The tray B idle rotation sensor (PI18) is faulty. The tray B lower limit sensor (PI24) is faulty. The tray B paper sensor (PI17) is faulty. Try operating copier without finisher or contact an technician to repair finisher.