Question about HP LaserJet 2820 Printer

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Red dots on left of page

Whenever I print in colour I get a series of evenly spaced red dots all down the left side of the page. It doesn't happen when I pring in black. I have removed and cleaned all cartridges and the parts of the printer I can get to.

The dots do not look like residue from ink on a roller etc but look like small commas (,) and the density of the printing is the same on each dot (no fade).

Any ideas would be appreciated.


Posted by on

  • ukk9 Jan 25, 2008

    The distance is 34.5mm between the dots. Thank you for your assistance.


  • Anonymous Mar 27, 2014

    I have black dots evenly spaced don the page about 4 inches from the right margin in portrait. How do I get rid of them.



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Hi, I am having the same problem, but my service is locked.  How do i figure out what the code is?  i don't have the manual

Posted on Feb 03, 2008


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You need to measure the distance between two dots (In milimeters if possible). After that I may be able to determine what is causing the problem.

Posted on Jan 24, 2008

  • Dean Joly
    Dean Joly Jan 25, 2008

    According to HP the first thing to check is that you have the printer set to the right paper type, this can be changed in the print properties of the printer driver.

    Next is that there might be a dirty roller that will clean itself over time, but you can clean the printer more thoroughly.

    Here are the two methods for cleaning the device:

    To clean the paper path from HP Toolbox

    Use HP Toolbox to clean the paper path. This is the recommended cleaning method. If you

    do not have access to HP Toolbox, use the method in To clean the paper path from the

    device control panel.

    1. Make sure that the device is turned on and in the Ready state.

    2. Open HP Toolbox.

    3. On the Troubleshooting tab, click Maintenance, click Cleaning Page and then click

    . A page with a pattern prints from the device.

    4. At the device, remove any print media that might be in tray 1.

    5. Remove the page that printed and load it face-down into tray 1.

    6. At the computer, click Clean.

    To clean the paper path from the device control panel

    If you do not have access to HP Toolbox, you can print and use a cleaning page from the

    device control panel.

    1. Press MENU.

    2. Use the < or the > button to find the Service menu.

    3. Press ENTER.

    4. Use the < or the > button to find Cleaning Mode.

    5. Press ENTER.

    6. Load plain letter or A4 paper when you are prompted.

    7. Press ENTER again to confirm and begin the cleaning process.

    A page feeds through the printer slowly. Discard the page when the process is completed.

    After that they suggest that the imaging drum might be low but since you problem goes away when doing black and white prints then I would not suspect the drum. They also suggest the fuser but again, if the fuser was faulty you would see the defect on black pages two.

    If cleaning doesn't fix the problem then I would suggest changing the magenta toner cartridge first.



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