On Fri, 3 Oct 2014 17:17:40 +0200, (pierre
lemercier) wrote:

Keith Nuttle wrote:

On 10/3/2014 5:40 AM, pierre lemercier wrote:
I just bought a HP Color LaserJet Pro M177fw;installation ok but if I
use this device to make photocopies with the document feeder I get a
black band in the middle of the output sheet.
Was the original damaged?
This is not the case if I
use the flatbed scanner.

Any solution?

This is a common problem with a copying machine. I believe the solution
is to clean the rollers on the feed.

Thanks. it works after a complete cleaning of the rollers.
I'm glad that you got things fixed, but I don't understand exactly
what happened.

Did the originals get visibly damaged before you cleaned the
rollers?

Are the rollers in back of the page being scanned?

Are the rollers actually in view of the scanning window?
(If the rollers were supposed to be white and were black
I can see that "bleed through" could cause the copy to
be dark, but unless you are using very thin paper it seems
like the copy should only be slightly noisy in the affected
band.)

If the originals looked OK after a marred copy was made using
the document feeder, did copies make from the flatbed also
look OK? If you don't know, could you try making a copy
using the flatbed from an original that you only made a marred
copy using the feeder?

(I've seen copiers mar originals in a visible manner, but
I am curious as to what the rollers due to affect the copies
without permanently visibly affecting the originals.)