HP color LaserJet 9500mfp Manual De Instrucciones página 24

5) Make sure that the four blue levers above the image-drum door are in
the horizontal position. Align the yellow drum with the correct slot,
arrow-end first. Rest the end of the drum flat on the image-drum door.
Note: The four blue levers must be in the horizontal position so that the
image drums can be installed.
6) Hold the gray protective cover in place with one hand and use the palm
of your other hand to slide the drum firmly and completely into the MFP.
Note: If the drum does not fit into the slot, make sure that you are
installing the correct color drum in the correct slot, and that you have the
drum aligned correctly.
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