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252 Chapter 9 – Image quality EN
• The priority input tray is not in place.
• The toner density is set incorrectly.
• The media basis weight is too high.
• The humidity level is too low.
• The toner cartridge is defective.
• The media does not meet HP paper specifications or is stored
improperly.
• The laser/scanner assembly or ECU is defective.
• The toner cartridge is defective or it was improperly installed.
• The printer needs to be cleaned.
• The fusing assembly is dirty or defective.
• A gear is damaged.
• A roller is damaged.
3100 and 3150 series only
• Horizontal lines appear in the margins and across entire pages of
faxes, copies, and scans.
– Clean the contact image sensor.
– Recalibrate the scanner.
– Check for a problem in the contact image sensor.
Gray background
Horizontal black lines or smears