Quote Originally Posted by teebee1234 View Post
If the dark band is only when copying from the glass then another possibility is that the white platen sheet is deformed/rippled or not sitting flush with the scanner surface . It will allow room light through and give you that condition. Would help to post an image and a few more details.
On the right track. It is light infiltration akin to the old Ricoh Aficio 1045 when we had to pull the entire scanner up because of poorly designed support for the scanner/df assy.