Brother HL-5250DN Series - Manual (Page 102)

7. Troubleshooting
94
Black toner marks across the
page
„ The drum unit may be damaged. Put in a new drum unit. See Replacing the drum
unit on page 68.
„ Make sure that you use paper that meets our specifications. See About paper on
page 5.
„ If you use label sheets for laser printers, the glue from the sheets may sometimes
stick to the OPC drum surface. Clean the drum unit. See on Clean the drum unit
as follows: on page 93.
„ Do not use paper that has clips or staples because they will scratch the surface
of the drum.
„ If the unpacked drum unit is in direct sunlight or room light, the unit may be
damaged.
Black lines down the page
Printed pages have toner stains
down the page.
„ Clean the primary corona wire inside the drum unit by sliding the blue tab. See
Cleaning the corona wire on page 77.
„ Make sure the primary corona wire cleaner is at the home position (a).
„ The drum unit may be damaged. Put in a new drum unit. See Replacing the drum
unit on page 68.
„ The toner cartridge may be damaged. Put in a new toner cartridge. See
Replacing the toner cartridge on page 63.
„ The fuser unit may be smudged. Call your dealer or Brother Customer Service.
Page skewed
„ Make sure that the paper or other print media is loaded properly in the paper tray
and that the guides are not too tight or too loose against the paper stack.
„ Set the paper guides correctly. See Printing on plain paper, bond paper or
transparencies from Tray 1, 2 or 3 on page 9.
„ If you are using the multi-puroise tray, see Printing on plain paper, bond paper or
transparencies from the MP tray on page 12.
„ The paper tray may be too full. See Printing on plain paper, bond paper or
transparencies from Tray 1, 2 or 3 on page 9.
„ Check the paper type and quality. See About paper on page 5.
Curled or wavy
„ Check the paper type and quality. High temperatures and high humidity will cause
paper to curl. See About paper on page 5.
„ If you do not use the printer often, the paper may have been in the paper tray too
long. Turn over the stack of paper in the paper tray. Also, fan the paper stack and
then rotate the paper 180
° in the paper tray.
Examples of poor print
quality Recommendation
ABCDEFGH
abcdefghijk
A B C D
a b c d e
0 1 2 3 4
ABCDEFGH
abcdefghijk
A B C D
a b c d e
0 1 2 3 4
ABCDEFGH
abcdefghijk
A B C D
a b c d e
0 1 2 3 4