Lexmark C520 Series, Service Manual

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Service Manual
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Main Components
System card
The system card provides the intelligence of the printer. Command and control signals originate in the system
card that make print media travel possible. The system card controls the timing of the print media during the
printing so the media arrives at certain positions in the print process at certain times.
Paper tray
Houses the print media.
Paper pick mechanism
Picks the print media from the paper tray. The paper pick mechanism contains the paper pick (input) sensor and
the multifunction transparency sensor.
Bump aligner roll
The bump aligner roll advances the print media onto the transfer belt and corrects any media skew as it comes
out of the paper trays or MPF.
Transfer belt
The function of the transfer belt unit is two fold: 1) the transfer rolls (located inside the transfer belt unit) are an
integral part of the EP process and 2) the transfer belt advances the print media through the printer.
Fuser
The fuser bonds toner to the print media and advances the print media through the last portion of the paper
path. The paper exit sensor is also located in the fuser and a flag is present on all fusers that activates the bin
full sensors on network model printers.
Duplex
Duplex capability is present only on the C524dn or C524dtn model printers. The duplex function is built into the
front access door and uses a peekaboo method for rerouting the paper down and back through the paper path
for a second time. To accomplish the peakaboo method, the paper is fed partially out of the printer and is then
reversed back into the printer.