HP Officejet J5740 All-in-One Printer - Manual (Page 122)

To clean the glass strip inside the automatic document feeder
1. Turn off the HP All-in-One, and unplug the power cord.
NOTE: Depending how long the HP All-in-One is unplugged, the date and time
might be erased. You might need to reset the date and time later, when you plug
the power cord back in.
2. Lift the cover of the automatic document feeder.
3. Raise the lid, as if you were loading an original on the glass.
4. Lift the automatic document feeder mechanism.
Chapter 10
120 Maintain the HP All-in-One