Samsung SCX-4521F Condition Suggested solutions Background, Scatter Distributed on the printed

	Condition		Suggested solutions
Vertical lines If black vertical streaks appear on the page:
			• The drum inside the toner cartridge has probably been
		AaBbCc	scratched. Remove the toner cartridge and install a
		AaBbCc	new one. See “Replacing the Toner Cartridge” on
		AaBbCc	page 8.4.
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		AaBbCc	If white vertical streaks appear on the page:
			• The surface of the LSU part inside the machine may be
			dirty. Clean the LSU (“Cleaning the Inside” on
			page 8.2). Contact a service representative.
Gray			If the amount of background shading becomes
background			unacceptable:
			• Change to a lighter weight paper. See “Paper
	AaBbCc		Specifications” on page 10.3.
	AaBbCc		• Check the machine’s environment: very dry (low
	AaBbCc		humidity) or high humidity (higher than 80% RH)
	AaBbCc		conditions can increase the amount of background
	AaBbCc		shading.
			• Remove the old toner cartridge and install a new one.
			See “Replacing the Toner Cartridge” on page 8.4.

Condition	Suggested solutions
Background	Background scatter results from bits of toner randomly
scatter	distributed on the printed page.

	• The paper may be too damp. Try printing with a
A	different batch of paper. Do not open packages of
	paper until necessary so that the paper does not
	absorb too much moisture.
	• If background scatter occurs on an envelope, change
	the printing layout to avoid printing over areas that
	have overlapping seams on the reverse side. Printing
	on seams can cause problems.

•If background scatter covers the entire surface area of a printed page, adjust the print resolution through your software application or the printer properties.

Misformed	• If characters are improperly formed and producing
characters	hollow images, the paper stock may be too slick. Try a
	different paper. See “Paper Specifications” on
	page 10.3.
	• If characters are improperly formed and producing a
	wavy effect, the scanner unit may need service. For
	service, contact a service representative.

Toner smear		• Clean the inside of the machine. See “Cleaning the
		Inside” on page 8.2.
		• Check the paper type and quality. See “Paper
		Specifications” on page 10.3.
		• Remove the toner cartridge and install a new one. See
		“Replacing the Toner Cartridge” on page 8.4.
Vertical		If marks repeatedly appear on the printed side of the
repetitive		page at even intervals:
defects		• The toner cartridge may be damaged. If a repetitive
		mark occurs on the page, print a cleaning sheet several
	AaBbCc	times to clean the cartridge; see “Cleaning the Drum”
	AaBbCc	on page 8.5. After the printout, if you still have the
	AaBbCc	same problems, remove the toner cartridge and install
	AaBbCc	a new one. See “Replacing the Toner Cartridge” on
	AaBbCc	page 8.4.

•Parts of the machine may have toner on them. If the defects occur on the back of the page, the problem will likely correct itself after a few more pages.

•The fusing assembly may be damaged. Contact a service representative.

•If you use inferior quality paper; see “Cleaning the Drum” on page 8.5.

Page skew

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Curl or wave

Wrinkles or creases

•Ensure that the paper is loaded properly.

•Check the paper type and quality. See “Paper Specifications” on page 10.3.

•Ensure that the paper or other material is loaded correctly and the guides are not too tight or too loose against the paper stack.

•Ensure that the paper is loaded properly.

•Check the paper type and quality. Both high temperature and humidity can cause paper curl. See “Paper Specifications” on page 10.3.

•Turn over the stack of paper in the tray. Also try rotating the paper 180° in the tray.

•Ensure that the paper is loaded properly.

•Check the paper type and quality. See “Paper Specifications” on page 10.3.

•Turn over the stack of paper in the tray. Also try rotating the paper 180° in the tray.

9.9 Troubleshooting