Lexmark 502n copies whole Pages black, but prints ok demos and setup recount

[itsbasix]

Hi guys,
All of a sudden my Lexmark 502n started giving out whole black pages when copying documents, while it works normally If you print something. Also it is a lot slower than before while copying. Already checked printing settings, density, quality,etc...Any advice?
Thank you and sorry for my bad English but I'm not an English native speaker.

[fixthecopier]

The scanner lamp is most likely bad.

[itsbasix]

I thought that too, but it actually lights up properly while scanning, and every now and again the machine starts working normally for a bit...could it be some flat/connection problem? Thank you for your answer