Lexmark X543 Service Manual

Diagnostic aids3-59
Lexmark confidential until announce7525xxx
with the ADF scan sensor ensure that the media is travelling at the correct speed through the scan area. The 
speed the document travels through the ADF scan area is dependent on the image DPI specified by the user.
7. After a predetermined number of counts, the media reaches the scan area and the image acquisition process 
is initiated. While the image acquisition process is executing, the ADF scan sensor is being polled to determine if 
the...

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Color theory
What is RGB color?
Red, green, and blue light can be added together in various amounts to produce a large range of colors 
observed in nature. For example, red and green can be combined to create yellow. Televisions and computer 
monitors create colors in this manner. RGB color is a method of describing colors by indicating the amount of 
red, green, or blue needed to produce a certain color. 
What is CMYK color?
Cyan, magenta,...

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My color transparencies seem dark when they are projected. Is there anything I can 
do to improve the color?
This problem most commonly occurs when projecting transparencies with reflective overhead projectors. To 
obtain the highest projected color quality, transmissive overhead projectors are recommended. If a reflective 
projector must be used, then adjusting the Toner Darkness setting to 1, 2, or 3 will lighten the transparency. 
Make...

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How can I match a particular color (such as a corporate logo)?
From the printer Quality menu, nine types of Color Samples sets are available. These are also available from the 
Color Samples page of the Embedded Web Server. Selecting any sample set generates a multiple-page printout 
consisting of hundreds of colored boxes. Either a CMYK or RGB combination is located on each box, depending 
on the table selected. The observed color of each box...

Repair information4-1
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4.  Repair information
Warning:  Read the following before handling electronic parts.
Handling ESD-sensitive parts 
Many electronic products use parts that are known to be sensitive to electrostatic discharge (ESD). To prevent 
damage to ESD-sensitive parts, use the following instructions in addition to all the usual precautions, such as 
turning off power before removing logic boards:
Keep the ESD-sensitive part in its original shipping...

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Removal procedures
Notes:
Some removal procedures require removing cable ties. You must replace cable ties during reassembly to 
avoid pinching wires, obstructing the paper path, or restricting mechanical movement.
Remove the waste toner bottle, color toner cartridges, imaging unit, and media tray before removing other 
printer parts. The imaging unit should be carefully set on a clean, smooth, and flat surface. It should also 
be protected...

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4.Remove the five screws (A) from the cable cover.
5.Remove the cable cover.
6.Remove the screw (B) securing the right restraining strap to the front cover.
Note:  Support the door with one hand after removing the screw holding the restraining strap. This is the 
longest screw of the eight. The two flat head Phillips screws are used in the door hinge.
7.Remove the two screws (C) securing the interlock and cable.
8.Route the cable through...

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Front middle cover removal
1.Open the front cover.
2.Remove the five screws (A) attaching the front middle cover to the lower front cover.
3.Pull the front middle cover away from the front cover.
Left cover removal
1.Remove the media tray.
2.Open the front cover.
3.Position the printer with the left side hanging over the edge of the table.
A 

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4.Remove the three screws (A) on the rear side of the left cover.
A 

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5.Remove the screw (B) on the bottom of the cover. 
6.With a hand on the bottom of the cover, ease the cover over the off/on switch, and rotate the cover away 
from the printer.
Warning:  Be careful not to damage the rear tab at the upper rear side of cover.
Installation note: When replacing the left cover, flex the cover slightly to engage the tab near the power 
swi tc h .
B