Lexmark T63 Series, Service Manual

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Diagnostic information
2-83
4060- xxx
Print quality—banding
Service tip: Banding is difficult to detect except on a page with a uniform gray or a large amount of
graphics printed on the page. Banding is primarily due to a variation in the speed of the paper as it
feeds through the printer, especially in the development and transfer process. Inspect the alignment
assembly, main drive assembly, and all other paper feed components for signs of wear, dirt, binds, or
damage, especially the drive gears. Banding appears as light or dark horizontal lines on a uniformly
gray page.
Banding can also be caused by a defective charge roll brush contact or HVPS. Check the charge roll
contact for damage and for proper connection to the HVPS and print cartridge.
Print quality—black bands on outer edges of the page
This print quality problem appears as vertical black bands on one or both sides of the copy and can
be wide, narrow, light, or dark.
Print quality—residual image
Service tip: Install a new print cartridge if available before doing this service check. Residual image
can be caused by the photoconductor, cleaning blade, and other parts inside the print cartridge.
FRU Action
1 Charge roll counterbalance
springs If the problem is just on one side of the page, check the charge roll
counterbalance spring on that side. You can check to see if enough
force is being applied to the charge roll by applying a slight
downward pressure with your finger to the charge roll link arm that
the spring is attached to while you run a print test sample. See if the
problem changes or goes away. If this fixes or changes the problem,
then check the springs and charge roll link arm assemblies for binds
or defective parts. Replace as necessary.
2 Charge roll assembly
Charge roll link arm Check the charge roll for toner buildup or other contamination on the
outer edges that correspond to the bands on the page. Check the
charge links and arms for proper operation, binds or incorrectly
mounted counterbalance springs. Repair or replace as necessary.
3 HVPS Check the following voltages at J22-8 on the system board:
• Printer Idle
J22-8 measures 0 V dc
• Printer Printing Test Page
J22-8 voltage changes from 0 V dc to +4 V dc
If the voltage does not vary, check the continuity of line J22-8 in the
front cable harness. If there is no continuity, replace the cable
harness. If there is continuity, replace the HVPS. If this does not
correct the problem, replace the system board.
Turn the printer off and check the resistance between J22-7 and
printer ground. The resistance measures approximately 0 ohms. If
incorrect, make sure the system board is mounted correctly and
securely grounded. If correct, replace the system board.
FRU Action
1 Hot roll fuser assembly Check the fuser assembly for toner contamination. The hot roll
especially might cause toner to be retained and deposited on the
page.