Printer not printing after cartridge change

[HappyClouds]

My printer cartridges were showing low ink, I changed the black first, and the printer wouldn't print at all. Then I changed the 3 colour cartridges, still no print. Did the clean, align printheads, then a print quality report. The print quality report says cartridges are genuine, ink levels full, the print colour boxes are full and shaded correctly for the 3 colours, but empty for the black box.
However what is really strange is that the written text is printed in black correctly, and all the box outlines etc are printed in black. Also strange that the 3 colours are all showing correct but when I try to print anything I just get a completely blank page.

Next I changed the black cartridge again, as advised by online support doc, in case a cartridge problem, but exactly the same blank page. 

Been going on a few days now, as I have unplugged it, let it reset etc, nothing worked yet.

Has anyone had this issue?

Thanks in advance! 🙂 

[Bob_Headrick]

The troubleshooting steps in the document here may help resolve black not printing on your Photosmart 6520.  Note that the diagnostic page uses a mixture of black and  color inks to print the information.  This is so the page can be read even if black (or one or more colors) are not printing properly.  In a pinch you can get a similar effect by choosing glossy photo paper as the media type.  This will force even black text to be printed with color ink. 

If the standard troubleshooting did not resolve black not printing I would suggest removing the black cartridge.  Turn it over and examine the area around the ink port.  There are four orange plastic spots, left over from the protective cap.  Make sure these are flush with the cartridge body, if not carefully trim them flush.  If the plastic nubs protrude they can prevent the cartridge from seating properly.  Before replacing the cartridge in the printer dribble a few (maybe four) drops of hot water into the ink port in the printer and two drops into the ink port on the cartridge then snap the cartridge back in position.  

It may also help to manually clean the printhead as described in the post here. 

I have also seen cases where leaving the printer overnight after the cleaning cycles allows black to recover.

If none of the above restores black printing your printer will likely require repair or replacement.