My officejet pro 6978 will not print black even though cartridge indicates nearly full

[gmill]

My Officejet Pro 6978 quit printing black even though the black cartridge indicates nearly full. All color cartridges also indicate nearly full and are printing fine. Only the black quit working in both print and copy modes. This is the second time this has happened. The first time I replaced the black cartridge with an HP 902XL and the printer began printing normally again. Receiving ink cartridges  from HP Instant Ink program.

[asmita6658]

Hi @gmill

Welcome to the HP Support Community. 

Try these steps - HP OfficeJet 6900 Printers - Black or Color Ink Not Printing, Other Print Quality Issues

Update the printer's firmware. Refer to this document for steps - HP Printers - Updating or Upgrading Printer Firmware 

Also, have you checked you HP Instant Ink account page? Your Instant Ink account page will have notifications if there are any issues with the account or recent cartridge shipment, it will even provide solutions on how to fix the issue. You may log in to your HP Instant Ink account page from here.

If the suggested information can't be found, please send us a private message with your Instant Ink account details or you may also respond to the private message I've sent out and I'll help you out, accordingly. Check next to your profile Name, you should see a little blue envelope, please click on it. 

Let me know. 

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