7.1.7. Vertical White Lines
Possible Cause (Scanner)
•
Defective image sensor element(s).
Action:
•
Replace the image sensor.
Possible Cause (Printer)
•
The laser optic components are dirty.
Action:
•
Clean the laser optic components.
7.1.8. Horizontal White Lines
Possible Cause (Printer)
•
The surface of the development roller is damaged or deformed.
•
The development bias is not stable.
•
Transfer bias is not stable.
Action:
1. Print a test pattern, and open the cover in the middle of printing.
2. Check if horizontal white lines (where toner is not adhered) appear on the
drum surface or not.
•
If they do, go to step 3.
•
If not, check the transfer roller surface and the transfer bias terminals
connections. If they are OK, check or replace the high voltage power
supply.
3. Check if horizontal white lines (where toner is not adhered) appear on the
development roller surface or not.
•
If they do, check if the development roller surface is not deformed. If it is
OK, check or replace the high voltage power supply.
•
If not, check for damage on the drum surface.
July 30th, 1996
TROUBLESHOOTING
COPY QUALITY TROUBLESHOOTING
7-7
