Oki C821 User Manual page 100

SYMPTOMS
Horizontal Lines and
spots appear
periodically.
White area of paper is
lightly stained.
Periphery of the letters
is smudged.
Toner comes off when
it is rubbed.
Glossiness is not
uniform.
POSSIBLE CAUSES
When the interval is about
94mm (4in), the image drum
(the green tube) is damaged
or dirty.
When the interval is about
30mm (1.2in), there may be
foreign particles in the image
drum cartridge.
When the interval is about
86mm (3.4in), the fuser unit
is damaged.
The image drum cartridge
has been exposed to light.
Paper contains static.
Too thick paper is used.
The toner is low.
The LED head is dirty.
The thickness and type of the
paper are incorrectly set.
Recycled paper is used.
The thickness and type of the
paper are incorrectly set.
Troubleshooting > 100
STEPS TO TAKE
Wipe it lightly with a soft cloth.
Replace the image drum
cartridge when it is damaged.
Open/close the top cover, and
print again.
Replace the fuser unit.
Replace the image drum
cartridge if the problem is not
resolved.
Use paper stored in proper
temperature and humidity
conditions.
Use thinner paper.
Open the top cover and tap the
cartridge a few times to evenly
distribute any remaining toner. If
symptoms persist, replace the
toner cartridge.
Wipe the LED head with a soft,
lint-free cloth.
Set the correct value of media
type and media weight in the
Media menu or set one value
lighter for media weight.
Set one value thicker for media
weight in the Media menu.
Set the correct value of media
type and media weight in the
Media menu or set one value
lighter for media weight.