HP LaserJet PRO M521 Repair Manua page 59

7.
Remove one screw on the left-side of the document feeder/scanner assembly.
NOTE:
Figure 1-64
8.
Slide the document feeder/scanner assembly back, and then pull up to remove.
Figure 1-65
ENWW
Rear-right document feeder/scanner ground screw shown still installed in this photo.
Remove the document feeder/scanner assembly (6 of 7)
Remove the document feeder/scanner assembly (7 of 7)
Removal and replacement procedures
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