Brother 1270N - Manual (Page 152)

CHAPTER 6 TROUBLESHOOTING
6-30
I-7 Black and blurred horizontal stripes
Possible cause Step Check Result Remedy Ground
contacts
Scratch on the
drum 1 Are the horizontal stripes at
94mm (photosensitive drum)
intervals? Yes The photosensitive
drum was scratched.
Replace the drum
unit.
Toner stuck on
the developer
roller 2 Are the horizontal stripes at
39mm (developer roller)
intervals? Yes After printing several
pages, the problem
will disappear.
If not, replace the
toner cartridge.
Scratch on the
heat roller 3 Are the horizontal stripes at
79mm (heat roller) intervals? Yes Replace the heat
roller.
Corona contact
failure 4 Are the charge electrodes
between the printer body and
the drum unit dirty? Yes Clean both electrodes.
➂
High-voltage
power supply
PCB failure 5 Is the problem solved after
replacing the high-voltage
power supply PCB? Yes Replace the high-
voltage power supply
PCB.
I-8 Black vertical streaks (in a gray background)
Possible cause Step Check Result Remedy
Ground
contacts
Translucent
stain on the
scanner window 1 Is there any dirt on the scanner
window? Yes 1) Clean the scanner
window.
2) If it is not effective,
replace the laser
unit.
Corona failure 2 Is the corona wire dirty? Yes Clean the corona wire
with the wire cleaner. ➁
User Check
(1) The drum unit may be damaged. Install a new drum unit.
(2) Check the paper used meets the recommended paper specifications.
(3) Clean the printer interior and the corona wire in the drum unit.