I have a brother hl-3040cn laser printer and it is printing a shadow of the print - any ideas how to resolve?

SOURCE: 3 - lines appears on pages when I print

I would suggest replacing the drum unit.

SOURCE: Brother printer prints solid black on one side

This is caused by a faulty drum/charging circuit or laser unit. The drum is positively charged with static electricity and a laser draws the image onto the drum (changing the charge to negative) the toner is positively charged to it will adhere to the negatively charged image which is now on the drum. your problem is that the drum is either not being positively charged or the laser is charging the whole drum. There is a corona wire on the drum, remove the drum, sweep the corona wire (there will be a tab that moves left and right) and try it again. next step is to replace the drum. if you dont have a spare drum or one from another printer then it may be more cost effective to buy another printer as drums are quite expensive and it may not even be the problem.

SOURCE: Brother HL 1440 Laser printer-horizontal black streaks

check your drum may the corona ware is broken . change the drum.

SOURCE: Brother HL-5250DN Laser Printer making noises and not printing

some gears are not in proper position , pull out the paper tray and closed it strongly .

SOURCE: Hi! the drum light on my Brother HL-2170 laser

1. Open Cover.
2. Press the Clear key to display drum status.
3. Press 1 (hold) on the telephone keypad.
4. When the display shows "ACCEPTED", close the front cover.
PRESTO!