HP 6978 not printing black

[Bob_Melton]

HP 6978 printer prints colors but not black.  I've run the alignment and printhead cleaning routines several times and I've put in a new black cartridge.  I've reset the printer to facotry defaults and updated the firmware.  Still does not print black.

[A_Gayathri]

Hi @Bob_Melton,

Welcome to The HP Support Community.  

Thank you for posting your query, I will be glad to help you.

I understand you've covered most of the common troubleshooting steps. If your HP OfficeJet Pro 6978 is still not printing black despite trying a new cartridge and running cleaning routines, 

here are a few additional things you can try:

• Check for Air Bubbles: Sometimes, air bubbles can get trapped in the printhead nozzles. You can try running a printhead cleaning cycle again, or use the printer's utility software to perform a deep cleaning.
• Inspect the Printhead: Remove the printhead and check for any dried ink or clogs. If you see any, gently clean the contacts and the printhead nozzles with a soft, lint-free cloth and a small amount of distilled water.
• Perform a Printhead Alignment: Sometimes, misalignment can affect printing. Go to your printer’s settings and perform another printhead alignment.
• Check for Firmware Updates: Ensure your printer firmware is up to date. Sometimes, new firmware updates can fix printing issues.
• Try a Different Black Cartridge: Although you’ve replaced the black cartridge, it’s worth trying a different one to rule out a faulty cartridge.
• Check Ink Levels: Even though the cartridge is new, ensure that the ink level indicators are correct and that the cartridge is installed properly.
• Inspect the Carriage Path: Make sure there’s no obstruction or residue blocking the printhead's path.

Refer to this document: HP OfficeJet Pro 6978 All-in-One Printer User manual 

I hope this helps. 

Take care and have a good day.

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. 

[Bob_Melton]

I've tried all of these things EXCEPT for removing the printhead.  I cannot find instructions anywhere online for how to do this. Any advice would be apprecitated.  Thanks!

[A_Gayathri]

Hi @Bob_Melton,

Thank you for your response, I appreciate your efforts. As the issue persists, I am sorry to hear that I'm sending out a private message to assist you with the next course of action. 

Please check your Private message icon on the upper right corner of your HP Community profile Next, to your profile Name, you should see a little blue envelope, please click on it or simply click on this link.

I hope this helps! Keep me posted for further assistance.

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos, Thumbs Up" on the bottom right to say “Thanks” for helping!