I have added paper to my samsung scx 4720 F printer ...And yet it is still calling for paper..
There is a paper sensor which either senses for paper either in the paper tray, or that the paper tray itself is in place. This is probably a switch or optical sensor with some sort of lever. If this lever is broken, or sensor defective, it will be unable to give a "paper present" signal to the logic circuitry.
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