Steaking on one side of a duplex scan, how do I clean the other side of the scanner?

[klotechie]

When I scan using the auto-document feeder only I get steaks on one side. I have cleaned the scanner glass, white plastic back, and both document feeder strips. Apparently, there is toner build-up on a place I cannot access. Is there a way to clean this so I no longer get toner streaks on my scans? When I do a one-sided scan I get the streaks. On a duplex scan, the streaks are on the same side, but not on the other side. This is an auto-duplex, so I don't have to manually flip the pages, if that helps.

[Valsimot · Accepted solution]

Open the top cover to access the scanning glass. Clean smaller glass on the left side, do not remove or damage plastic foul ( if present). If you are unsure where to look or clean load a sheet with steak and place it on the scanner big glass near the small glass and the streak on the paper should align with the dirt on a smaller glass that is causing the streak.