OfficeJet Pro 6978 only prints yellow and black colors

[KP2021]

OfficeJet Pro 6978 only prints yellow and black colors. I changed all the HP ink cartridges. Cleaned the printhead. Can't complete the printer alignment.

[Kumar0307]

@KP2021, Welcome to the HP Support Community! I’m here to help.

I understand the printer is not printing magenta and cyan. Make sure you are using HP ink cartridges.

Do you get any errors?

Kindly perform the steps mentioned in this document - Black or Color Ink Not Printing, Other Print Quality Issues

Clean the printhead up to 2 times and print a test page to check the result.

For the alignment to work, all 4 colors should print fine.

If the issue persists even after replacing the ink cartridges, I'm afraid this is a hardware issue with the printhead and it is non-removable on this model printer. 

If the printer is out of warranty, I suggest you upgrade the printer. You may visit Hp Store to check the available printers.

If the printer is working fine with a different set of ink cartridges, it could be the cartridges that are defective. In this case, please reach out to the HP Technical Support team in your region regarding the replacement options. 

You may create a case on the website to obtain a case number if required. Kindly watch this video to know how.

Keep me posted for any other assistance.

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Have a great day!