It may need the drum kit or some toner got to some roller.
http://www.brother-usa.com/printer/printer_detail_AREA=PRINTER_1&PRODUCTID=HL2040.aspx
The drum kit upsets some owners since it's a bit more expensive than toner but it doesn't last forever.
I found the HP method of drum and toner to avoid this issue.
Bob
Hello - This is a great laser printer; infallible service for nearly one year. But currently it's began to show a black 'speckled/smudged' area some 1"-2" wide descending vertically through the approximate middle of the page. I've checked the 'dummy' lights for 'toner' or 'drum' issues, but nothing there yet; actually it may be early in the problem, and just not showing yet. But wondered if anyone had similar problems, and what this line indicated? Thanks much -

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