Toner Is On The Back Of The Printed Page; Light Lines Or Streaks Appear On The Page - Lexmark C77x Service Manual

Toner is on the back of the printed page

Do the following steps before proceeding with this service check:
1.
Enter the Diagnostics Mode.
2.
Select Print Test, Tray 1, Continuous from the menu.
3.
Run at least 20 pages of text, and see if the problem remains.
•
If toner is still on the back of the printed page, proceed with this service check.
•
If the problem is on the top two inches of the page, replace the second transfer roll.
•
If the toner is "stringy" over the top half of the page, go to step 1.
Step Actions and questions
1 Media settings—Does the media setting match the
current media type?
2
Does resetting the media type fix the problem?
3 Fuser settings—Set the fuser to High in the CE menu.
Does setting the fuser to High fix the problem?

Light lines or streaks appear on the page

Single color streaks outside the printed page are most likely caused by a problem in the print cartridge. Replace
the print cartridge.
All the colors streaking at a different spot on each page is probably caused by a damaged ITU assembly.
Replace the ITU assembly. See
If only one color streaks in the printed area, go to step 1.
Step Actions and questions
1 Print cartridge check—Try a new print cartridge.
Does a new print cartridge fix the problem?
2 Printhead check—The printhead lens may be
contaminated by toner. Check for any signs of
contamination on the lens of the printhead.
Is the printhead contaminated?
"ITU assembly removal" on page
Yes No
Set the printer for Go to step 3
current media
type, and go to
step 2.
Problem resolved Go to step 3
Problem resolved Replace the fuser
assembly. See
"Fuser
assembly
removal" on
page
4-49.
Yes No
Problem resolved Go to step 2
Go to Clear the Contact your next
printhead lens level of support.
with a soft, lint-
free cloth.
Diagnostic information
5061
4-44.
2-103