Oki C 9400 User Manual page 292

The Media Weight setting is too high.
► If this happens only for a specific print job, reprint the job, changing the Media Weight
setting in the driver (File → Print → Properties [or Setup, or your application's equivalent])
to the next lowest value (e.g., change from Medium Heavy to Medium).
► If this happens frequently, enter the printer menu and change the media weight setting to
the next lowest value (see "Changing Media Weight Settings in the Menu" under "Print
Media").
In the PCL mode, the text is printing more of a dark brown than black.
The printer is set to print black using CMYK rather than black only.
► Enter the menu, go to PCL EMULATION and change the TRUE BLACK menu setting to
ON.
Vertical white stripes
LED head is dirty.
► Clean the LED heads with the lens cleaner pad (one is supplied with the printer, one is
supplied with each replacement toner cartridge) or a soft, lint-free cloth moistened with
rubbing alcohol.
Toner is low.
► Change the toner cartridge.
Image drum is damaged.
► Change the image drum.
Vertical fading.
The LED head is dirty.
► Clean the LED heads with the lens cleaner pad (one is supplied with the printer, one is
supplied with each replacement toner cartridge) or a soft, lint-free cloth moistened with
rubbing alcohol.
Toner is low.
► Change the toner cartridge.
Print media is unsuitable for printer.
► Use recommended media.
Faint printing.
The toner cartridge is incorrectly installed.
► Reinstall the toner cartridge.
Toner is low.
► Change toner cartridge.
The paper is moist.
► Replace the paper with dry paper. Be sure to store paper within specified temperature
and humidity levels.
The print media is unsuitable for printer.
► Use recommended media.
291