Brother MFC-9870 manual Print Quality Difficulties

124 C H A P T E R F I F T E E N

DIFFICULTY

SUGGESTIONS

Print Quality Difficulties
Printouts are too dark or light	Adjust the print conditions by setting the Print Density function, It has
	been factory set to the middle position. See “Setting the Print Density” in
	chap. 6.
Printed pages contain white stripes.	You may fix this by wiping the scanner windows with a clean soft cloth.
	(See “Regular Maintenance” and “Cleaning the Drum Unit” in this
	chapter.) If you still see white stripes or faint images and the display
	shows CHANGE DRUM SOON, replace the drum unit with a new one.
White Stripes or	Check the machine’s environment. Conditions such as humidity, high
Faint lmages	temperatures, etc. may cause this print defect to occur.
Printed pages are stained with toner	Clean the machine’s interior and the primary corona wire of drum unit.
or have vertical stripes.	See “Regular Maintenance” and “Cleaning the Drum Unit” in this
	chapter. Make sure that the tab of the corona wire is at the home position.
	If after cleaning, you still see dark stripes or toner stains and the display
	shows CHANGE DRUM SOON, replace the drum unit with a new one.
Dark Stripes or Toner Stains
Printed pages have white spots in	Make sure that you use paper that meets the specifications. Rough
black text and graphic areas.	surface or thick media can cause the problem. If you still see white spots
	and the display shows CHANGE DRUM SOON, replace the drum unit
	with a new one. Check the machine’s environment; conditions such as
	high humidity may cause this situation to occur.
White Spots
Toner scatters and stains the printed	Adjust the print conditions by setting the Print Density function. Clean
page.	the machine’s interior. See “Regular Maintenance” and “Cleaning the
	Drum Unit” in this chapter. Make sure that you use paper that meets
	specifications. See chap. 12. If you still have scattered toner and the
	display shows CHANGE DRUM SOON, replace the drum unit with a
Scattering Toner	new one. Check the machine’s environment; high temperature and high
	humidity conditions may cause this condition to occur.
The whole page is printed black.	Clean the machine’s interior and the primary corona wire of the drum
	unit. Also, do not use heat-sensitive paper as it will cause this problem.
	After cleaning, if the printed pages are still black or the display shows
	CHANGE DRUM SOON, replace the drum unit with a new one. The
Black Page	drum unit may be damaged.
Nothing is printed on the page.	Make sure that the toner cartridge is not empty. Wipe the electric
	terminals referring to “Regular Maintenance” and “Cleaning the Drum
	Unit” in this chapter. Make sure that a torn piece of paper does not
	remain on the scanner window.
White page
Printed pages are marked regular	Markings may disappear by themselves. Try copying at multiple pages
intervals.	to clear this problem. Markings may occur if the machine has not been
	used for a long time. A possible cause is that the surface of the drum is
	marked or damaged by excessive exposure to light. In this case, replace
Example of Regular Marking	the drum unit with a new one.