Dell 2130cn - Color Laser Printer User Manual page 109

5. Turn the four PHD lock levers counter-clockwise, and then pull the PHD unit out of the printer.
NOTE: Keep the PHD unit in the dark place. Avoid exposing the PHD unit to light.
6. Clean the feed roller inside the printer with a dry cloth.
7. Insert the PHD unit until it stops and turn the four PHD lock levers clockwise to lock the PHD unit.