Lexmark C91x Service Manual page 146

5055-xxx
Missing colors
Possible cause
Toner cartridge unit
Photodeveloper
High voltage unit
LED printhead unit
LED printhead controller board
High voltage unit (HVU)
Transfer belt unit
2-96
Service Manual
Action
Be sure the toner cartridge and the
PC drum unit are properly seated.
Be sure the contacts on the print unit
are clean. Be sure the print unit is
installed in the correct position. Run
a print test.
If the problem remains, switch the
toner cartridge with another color
and run a test print. If the new color
prints, replace the failing toner
cartridge.
If the problem remains, check the
connector on the high voltage unit.
Replace the high voltage unit If the
problem remains.
If the problem remains, replace the
printhead and EPROM.
If the problem remains, replace the
printhead controller board.
If the problem remains, replace the
high voltage unit.
If the problem remains, replace the
transfer belt unit.