OKI C821 Manual De Usuario

Troubleshooting > 99

Vertical white lines can 
be seen on the printed 
page.

The LED head is dirty.

Wipe the LED head with a soft, 
lint-free cloth.

The toner is low.

Open the top cover and tap the 
cartridge a few times to evenly 
distribute any remaining toner. If 
symptoms persist, replace the 
toner cartridge.

Foreign materials may be 
present in the image drum.

Replace the image drum 
cartridge.

Light-shielding film of the 
image drum cartridge is 
dirty.

Wipe the film with a soft, lint-
free cloth.

Printed images are 
fading vertically.

The LED head is dirty.

Wipe the LED head with a soft, 
lint-free cloth.

The toner is low.

Open the top cover and tap the 
cartridge a few times to evenly 
distribute any remaining toner. If 
symptoms persist, replace the 
toner cartridge.

The paper is not suitable for 
the printer unit.

Use recommended paper.

Printing is light.

The toner cartridge is not 
properly seated.

Reinstall the toner cartridge.

The toner is low.

Open the top cover and tap the 
cartridge a few times to evenly 
distribute any remaining toner. If 
symptoms persist, replace the 
toner cartridge.

The paper is moist.

Use paper stored in proper 
temperature and humidity 
conditions.

The paper is not suitable for 
the printer unit.

Use recommended paper.

Thickness and type of paper 
are inappropriate.

Set the correct value of media 
type and media weight in the 
Media menu or set one value 
thicker for media weight.

Recycled paper is being used.

Set one value thicker for media 
weight in the Media menu.

Partially faded images. 
White spots and lines 
appear in solid 
printing.

Paper is moist or dry.

Use paper stored in proper 
temperature and humidity 
conditions.

Vertical lines appear.

The image drum cartridge is 
damaged.

Replace the image drum 
cartridge.

The toner is low.

Open the top cover and tap the 
cartridge a few times to evenly 
distribute any remaining toner. If 
symptoms persist, replace the 
toner cartridge.