Troubleshooting and routine maintenance
107
Hollow print
Make sure that you use paper that meets our specifications. (See
Acceptable paper and other media on page 12.)
Choose Thick paper mode in the printer driver or in the machine’s Paper
Type menu setting, or use thinner paper t han you are currentl y using. (See
Paper Type on page 18 and Basic tab in the Software User’s Guide on the
CD-ROM.)
Check the machine’s environment. Conditions such as high humidity can
cause hollow print. (See Choosing a location on page 86.)
Clean the primary corona wire on the drum unit. (See Cleaning the corona
wire on page 126.) If the print quality has not improved, put in a new drum unit.
(See Replacing the drum unit (DR-520) on page 131.)
All black
Clean the primary corona wire on the drum unit. (See Cleaning the corona
wire on page 126.) If the print quality has not improved, put in a new drum unit.
(See Replacing the drum unit (DR-520) on page 131.)
The drum unit may be damaged. Put in a new drum unit. (See Replacing the
drum unit (DR-520) on page 131.)
White Spots on black text
and graphics at 3.7 in.
(94 mm) intervals
Black Spots at 3.7 in. (94 mm)
intervals
Dust, paper powder, glue, and so on may stick to the surface of the photosensitive
drum (OPC) and cause black or white spots to appear on printed documents.
Make a few copies of a blank, white sheet of paper. (See Making multiple
copies on page 74.)
If you still see the spots on printed documents after making multiple copies, clean
the drum unit (see Cleaning the drum unit on page 127).
If the print quality sti ll has not improve d you need to instal l a new drum. (See
Replacing the drum unit (DR-520) on page 131.)
Black toner marks across the
page
Make sure that you use paper that meets our specifications. (See
Acceptable paper and other media on page 12.)
If you use label sheets for las er printers, the glue from th e sheets may
sometimes stick to the OPC drum surface. Clean the drum unit. (See
Cleaning the drum unit on page 127.)
Do not use paper that has clips or staple s because they wil l scratch the
surface of the drum.
If the unpacked drum unit is in direct su nlight or room ligh t, the unit may be
damaged.
The drum unit may be damaged. Put in a new drum unit. (See Replacing the
drum unit (DR-520) on page 131.)
Examples of poor print
quality
Recommendation
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