No Image; Black Line - Lexmark C920 Service Manual

5056-XXX
Problem
Print on the page is skewed.
A white gap is noticeable
between color fills, due to poor
color registration.

No image

Possible cause
Moist paper
LED printhead
High voltage unit (HVU)
Printer controller board
Printhead controller board

Black line

Possible cause
Photodeveloper drum
• Fuser detach pawl
• Fuser roller surface
• Fuser thermistor surface
LED printhead
2-66
Service Manual
Action
Be sure the width guides in the paper tray or the multipurpose feeder fit
snugly against the media you loaded.
Be sure the charge roll or belt is seated properly.
Be sure all four corners of the printer are resting on a steady flat
surface.
Turn the printer off and back on. The printer calibrates the print head
timing, which may improve registration. Be sure that Auto Registration,
in diagnostic mode, is On.
Action
Be sure the printer is not in a damp environment and the paper is not
curled or wavy due to moisture. If necessary, inform the customer about
correct storage.
Be sure the LED printhead cable is securely connected to the printhead
controller board and LED printhead assembly. If the problem remains,
replace the LED printhead.
Be sure all the connectors to the high voltage unit are securely
connected. If the problem remains, replace the high voltage unit.
Be sure all connectors are securely connected to the printer controller
board. If the problem remains, replace the printer controller board.
If the problem remains, replace the printhead controller board.
Action
Clean any dirt from the drum surface. Replace it if it is scratched.
Remove any toner buildup. Replace the fuser.
Clean the LED printhead. Print a blank document. Replace the LED
printhead if a black line appears on the paper.