8550, 8550N, 8550DN, 8550GN, 8550MFP Printer

Problem
Horizontal lines or
streaks
Cause and Solution
A toner cartridge might be running out of toner. Check
the printer control panel display for a TONER LOW
REPLACE or TONER OUT REPLACE
message. Replace the toner cartridge indicated on the
printer control panel display. Do not shake the toner
cartridge in attempts to extend the cartridge life.
For more information on replacing the toner cartridge,
see the installation guide included with the toner
cartridge.
Dark or light lines or streaks appear in colors, except
black. A toner cartridge might be defective. If the
problem persists, contact a local authorized HP dealer
or service representative for service.
White lines or streaks only appear in the black areas of
print, but not in color areas. Print the configuration page
five times. The defect should clear with continued
printing. Then reprint the print job. If the problem
persists, replace the black toner cartridge. If the
problem persists, contact a local authorized HP dealer
or service representative for service.
Dark or white lines or streaks in all colors, including
black. Print the configuration page five times. The
defect should clear with continued printing. If the defect
does not clear, turn the printer off and on to reset the
printer's density calibration. Make sure that the transfer
belt is seated properly (rest the ends of the belt into the
notches inside the printer). If the problem persists,
replace the imaging drum. For more information on
replacing the imaging drum, see the installation guide
included with the drum kit.
Light streaks in dark solid fill areas might indicate that
the post charger on the transfer drum needs to be
cleaned. Open and close the front door to complete a
printer self-cleaning cycle. If the defect does not clear,
clean the post charger. For information on cleaning the
post charger, see “Cleaning the Post Charger” later in
this chapter.
EN Print Quality Problems 189