

Confidential
9-33
I-6
Black and blurred vertical streaks
User Check
(1)  Clean the corona wire in the drum unit. 
(2)  Check that the wire cleaner is at the home position. 
(3)  Check that the toner cartridge is not empty. 
(4)  The drum unit may be damaged.  Install a new drum unit. 
(5)  The toner cartridge may be damaged.  Install a new toner 
cartridge.
Possible cause
Step
Check
Result
Remedy
Corona failure
1
Is the vertical block streak 
about 10mm wide? 
(Check if the wire cleaner 
is at its home position.) 
Yes Return the wire cleaner to its
home position.
Dirt in the 
paper feed 
system 
2
Is the paper tray or feed 
system on the drum unit 
dirty with toner? 
Yes Clean the toner off.
Scratch on the 
drum 
3
Is the drum surface 
scratched? 
Yes Replace the drum unit.
Cleaning 
failure 
4
Is the drum  surface dirty 
with toner in streaks? 
Yes Replace the drum unit.
Scratch on the 
heat roller 
5
Is the surface of the heat 
roller scratched? 
Yes Replace the fixing unit.
NOTE:
•
If you print he same pattern (especially vertical streaks) continuously, electrostatic charge 
performance of the drum will decrease temporarily and black vertical streaks may appear on the 
paper
•
This problem may occur with noise due to the corona wire being dirty.  In that case, clean the 
corona wire with the wire cleaner.