you can safely replace the pickup roller without stabilising the document scanner and the laser scanner.
replacing the pickup roller is a relatively simple job that is easily done by someone who is good with their hands or with a little common sense.
here is a video showing the procedure
and a link to buy the part
Black hair lines can come from what is called the slit glass. Does the line appear when you can from just on the glass? If that scan is OK and the line appears when you run through the document feeder than the small glass just before the top glass needs a good clean, or sometimes in the machine the optics has some dirt on it.
Ok I know how to fix this issue, this involves going into the registry editor, also only available in windows XP, so be careful!
Click START -> RUN and type in REGEDIT
Go to HKEY_LOCAL_MACHINE -> SOFTWARE -> BROTHER -> CONTROLCENTER -> (version number) -> (model number) -> DEVICEINFO
Look in the right hand window for ENABLEWIA, if the value is set to 0, set it to 1.
Reboot your computer, should be fixed!
unplug plug it back in, did you remove the protective cover and clean coria wire? http://welcome.solutions.brother.com/BSC/public/us/us/en/faq/faq/000000/000000/000065/faq000065_018.html?reg=us&c=us&lang=en&prod=dcp7020_us
Try cleaning the rollers. You can get cleaning paper(sticky on both sides) from an office supply store. Run it thru a couple of times to see if that solves the problem.
