User Troubleshooting For Quality - Lexmark C78x Service Manual

User troubleshooting for quality

The information in the following table may help you solve print quality problems. If these suggestions still do not
correct the problem, call for service. You may have a printer part that requires adjustment or replacement.
Quality troubleshooting
Symptom
Repeating defects
Color misregistration
ABCDE ABCDE
ABCDE
ABCDE
White or colored line
ABCDE
ABCDE
ABCDE
Cause
Either the print cartridges
are defective, the image
transfer unit and transfer
roller are defective, or the
fuser is defective.
Color has shifted outside of
the appropriate area or has
been superimposed over
another color area.
Either the print cartridges
are defective, the image
transfer unit and transfer
roller are defective, or the
fuser is defective.
Solution
Marks occur repeatedly only in one color and
multiple times on a page:
• Replace the cartridge if the defects occur every:
- 48 mm (1.9 in.)
- 97 mm (3.8 in.)
Marks occur down the page repeatedly in all colors:
• Replace the transfer roll if the defects occur
every 60 mm (2.4 in.)
• Check the first transfer bellcranks and springs or
replace the image transfer unit if the defects
occur every 101 mm (4 in.)
• Replace the fuser if the defects occur every
148 mm (5.8 in.)
Marks occur on every third or sixth page in any
color:
Replace the image transfer unit.
Top to Bottom or Left to Right:
1. Re-seat the cartridges by removing them from
the printer and then reinserting them.
2. Adjust the Color Alignment under the Utilities
Menu.
1. Replace the color print cartridge causing the line.
2. If you still have the problem, replace the image
transfer unit and transfer roller.
3. If you still have the problem, replace the fuser.
Diagnostic information
5061
2-107