Thks for answer.
As a matter of fact it looks like something similar to your explanation.
Is there any way (or any manual to help) to disassemble the feeder to see what's going wrong and do any repair ?
Lift the lid like you were going to make a copy on the glass.
On the Lid where the paper feeds in from the DADF there should be a sensor that goes the full width, whatever the issue is, its on that bit (It scans the back half, front is done on the strip of glass to the left)
Since 3 days now i have a problem with the manual scanning.
When doing dual scanning, all the upper sides are OK but all of the backsides are stamped with a large bar half grey and half black on their left sides.
I have cleaned all of what can be done but this isn't a printing or inking problem. It is something like a real image covering nearly 5 cms of the whole left side of each backside.
This printer is from 2017 and all cartridges are new.
You'll find a 2 pages document to show precisely what the problem looks like : attached
Thks in advance for helping.