Lexmark C91x Service Manual page 145

Black line
Possible cause
Photodeveloper drum
• Fuser detach pawl
• Fuser roller surface
• Fuser thermistor surface
LED printhead
Black print
Possible cause
High voltage unit (HVU)
Sub-frame
Photodeveloper drum set
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.
Action
The printed paper has black print. Be
sure the high voltage unit is properly
connected. If the problem remains,
replace the high voltage unit.
If the problem remains, replace the
right sub-frame contacts.
If the problem remains after
replacing the sub-frame, be sure the
photodeveloper has clean contacts.
If necessary, replace the
photodeveloper.
Diagnostic information
5055-xxx
2-95