Lexmark C77X, Service Manual

Page: 309 / 480

Repair information
4-77
5061
13.
With one hand, bias the new printhead against the front and rear adjustment screws of the printhead
alignment assembly.
Note: Using a consistent force on the front and back of the printhead is important and will reduce the
number of interations.
14.
While maintaining bias pressure, tighten the right rear printhead mounting screw. Then tighten the front
screw followed by the left rear screw.
15.
Securely close the front cover assembly.
16.
Print the Mechanical Alignment Test page:
a.
Enter Diagnostics Mode (Turn the printer off, press and hold and , turn on the printer, and
release the buttons in about 10 seconds or until the clock face appears on the display).
b.
Select MISCELLANEOUS TESTS , and then select Printhead Inst .
The Mechanical Alignment Test page prints and can be used to determine the printhead alignment.
This page contains information for black (K), magenta (M), cyan (C), and yellow (Y) printheads.
c.
Look at the line pertaining to the color of printhead you are replacing.
The goal is to get the vertical line that runs from “REAR SIDE” to “FRONT SIDE” between 1 and -1 for
both front and rear.
For example, the following is a sample of the magenta “FRONT SIDE” with the vertical line at +5.
d.
If the line is outside of this range, turn off the printer, loosen the printhead mounting screws, and turn
the adjustment screw of the printhead alignment assembly as indicated by the Mechanical Alignment
Test page.
In the example above, the vertical line is at +5. Therefore, turn the front adjustment screw clockwise
five full turns. If the vertical line had been at -5 it would indicate you should turn the adjustment screw
five turns in a
counter clockwise direction. After adjusting the screw for the front and similarly
determining the adjustment and making it for the back, go to step 13.