M476dw First page is covered with solid black horizontal bars, almost covering the whole page

[dgrrr1]

 

 

 

M476dw First page is covered with solid black horizontal bars, almost covering the whole page

This HP color LaserJet MFP M476dw has three old mostly empty color toner cartridges. The black toner cartridge is new. The customer swears that the problem was happening with the previous black toner cartridge as well. (Although I couldn’t get the problem to happen when I had the old black cartridge inserted.)

These black horizontal bars cover most of the page; there’s only a couple of thin strips or you can see the white page underneath.

When it happens, it only happens on the first page, then the second page is better &  the third page is fine.

This problem happens with printing and photocopying.

After I reset the printer and reseated the cartridges, the computer went through a initialized, cleaning, and calibration process. This seemed to fix the black bar problem.

But then the black bars came back shortly later, after printing a few more jobs.

The color toner cartridges are old, and their rollers have inconsistent coloring, as if something is worn away. I.e. the cyan color cartridge roller is mostly cyan but has parts of it that are yellow.

The color cartridges rollers also seem to have a lot of black ink on them. I tried to clean out as much as I could By blowing out the excess, and manually turning them and wiping them. But there’s always a little bit of what appears to be black toner left, even when I turned & wiped around a full 360° of roller.

So my main suspect seems to be the color cartridges – except, even so, why would the “black bars” problem suddenly come back in full force? Between print jobs?

When I ran the cleaning/calibration process a second time, the black bars went away as before.  I also reset the printer to default settings, and told the printer to only use the black toner cartridge (through the printer device panel). But I’m still concerned the customers gonna call me tomorrow and say that the black bars are back.

[dgrrr1]

PS from the OP:  Obviously they’re trying to avoid buying new color cartridges as they only print black-and-white these days. I tried printing without the cartridges installed but that is not allowed.

Also, the printer makes grinding/ moaning noises when it’s initializing/recalibrating, but it’s nothing I haven’t heard from other printers. But the owner  thinks that the noise is relatively new.

[Repairatrooper]

That black cartridge you are showing the picture of is garbage. The drum unit should have a consistent green/blue color. The tan colored areas are missing the photosensitive coating.  If that is the new cartridge, return it to the vendor you bought it from and get it replaced. I bet even money that is a refurb from a drill and fill shop.

[dgrrr1]

(FYI that is the cyan / blue toner cartridge in the photo. The magenta & yellow also have the yellow striping where there should be blue, but not as bad.  I kept turning & wiping that ?black toner  off, until there was much less of it.  But there's still a little ?black toner left on the colored toner rollers when I keep turning the through the cartridge.)

[dgrrr1 · Accepted solution]

The following forum page contains the same issue, and the solution from HP. 

I have excerpted the summary below.

My client has replaced the color cartridges and everything is fine now.

————————

https://h30434.www3.hp.com/t5/LaserJet-Printing/hp-laserjet-pro-cm1415fnw/td-p/2915287/page/2

This looked very much like a black toner cartridge problem but it is NOT.  The problem is that the color cartridges, while not used very much in your everyday printing, have become physically worn out.  Two things happened.  The cartridge has an internal container for waste toner and that container is completely full, even bulging and warping the cartridge shape.  Second, the greenish drum that is used to capture the image and place it on an internal belt then finally on your paper has been worn through.  This wear allows the charging current to flow in unexpected ways and basically "pulls down" the power supply that is charging the black drum.  The areas of black printing during parts of the day are caused by the black drum not getting the full charge it needs to print.  There are theories why this self heals during the day only to come back, but basically replacing the 3 color cartridges is the solution.