Dell 5310n - Workgroup Laser Printer B/W Service Manual page 258

Replacement
Move the narrow media flag out of the way to clip the sensor securely into the cover.
1.
Connect the fuser narrow media cable.
2.
Snap the bottom fastener of the sensor cover into place in the lower exit guide, and rock the cover up until
3.
the top fastener snaps securely.
Replace the screw securing the sensor cover.
4.
Service Manual
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