LASERJET PRO 400 M425 MFP-BLACK OR DARK PAGES WHEN USING THE SCANNER

Hi.

I am servicing a LJ Pro 400 M425 MFP and when the user is trying to scan or copy, she get a black page or background on the pages.

When printing, no problem it print well. Any idea about it?

Could it be the scanner itself or the cable connected to the scanner?

Thanks for helping.