
Chapter 6
6 - 12
All black
Clean the primary corona wire on the drum unit. (See Cl eaning the corona wir e on
page 6-19.)
If the print quality has not im proved, install a new dru m unit. (See Replacing the
drum unit (DR-2000) on page 6-23.)
White Spots on black text and
graphics at 78.5 mm
intervals
Black Spots at 78.5 mm
intervals
Cleaning the drum unitDust, paper powder, glue, and so on may stick to t he surface of the photosensi tive
drum (OPC) and cause black or white spot s to appear on prin ted documents.
Make a few copies of a blank, white sheet of paper. (See Making multiple copies
on page 3-1.)
1 Remove the drum unit and t oner cartridge as sembly, and the n remove the tone r
cartridge from the drum unit.
2 Position the print sample in front of the drum unit so you will know the exact
position on the drum that is causing the poor print.
3 Turn the black gear on th e drum as you chec k the surface of the OPC drum.
Do not touch the OPC dr um with your finge rs.
4 When you find the substance on the drum surface that matches the print
sample, gently dab the surface of the OPC drum with a cotton swab that is lightly
dampened with isopropy l alcohol.
Do not use a scrubbing or wiping motion because thi s might damage the
drum.
Do not try to clean the sur face of the OPC drum with a sharp object , such as
a ball-point pen, because this might cause permanent damage to the drum
unit.
If the print quality still has not improved you need to install a new drum.
(See Replacing the drum unit (DR-2000) on page 6-23.)
Examples of poor print quality Recommendation
78.5 mm
78.5 mm
78.5 mm
78.5 mm
OPC drum surface