HP OfficeJet Pro 6978 stopped printing blue/cyan

[DreadfulSpiller]

Our OfficeJet Pro stopped printing blue.  After reading several posts here, we tried the following:

1.  Run the printer head cleaning.  We did this from two different computers as well as directly from the printer screen.  It took us through 3 stages of cleaning.  The test page after the first cleaning didn't show any blue box at all, the second test showed a thin line, and the third test showed a little bit more but not much.  Overall I think we ran the 3 stage cleaning cycle 7-8 times.

2.  Complete shutdown/restart.  Per the instructions in the forum, we unplugged both ends of the power cords, let the printer set for 3-5 minutes, held the power button down for 30 seconds (to get rid of any remaining charge), and then reinstalled the cord and started up the printer again.  

Neither of these solutions helped.  Our printer is still not printing any blue, except for the thin line on the 2nd and 3rd stage of the cleaning test sheets.  This didn't happen all at once - it started with blue/pink streaks across our printed pictures and blue ink fading to pink on documents. 

Appreciate any advice we can get!

[TEJ1602]

@DreadfulSpiller, Welcome to HP Support Community!

If you have already performed the steps from the document No black ink, wrong colors, other print quality issues, and the issue persists, it could be a hardware failure.

Please reach out to the HP Support in your region regarding the service options for your printer.

Hope this helps!

Please click “Accepted 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!

[dmdavie1]

I have the same problem. The cyan doesn't show up on printing tests. It does, however, print in pink. The other three cartridges print perfectly. I've just replaced all four cartridges so they're new. I've tried the plug in/plug out/restore power testing. Nothing seems to work.

[JohnM357]

Could this be a print head (not cartridge) problem?  I'm a user, not an expert.  But if the software clean/diagnose options don't work then I would think hardware service is needed (head replacement or fixing some of the ribbons/cables connected to the print head) based on the Googling/Youtube searches I've done on similar issue.

[dmdavie1]

Thanks very much for your response. I've just ordered an independent printhead cleaning system made to work for the 6978. Hopefully, this works. If not, it probably is another problem within the printhead. I don't think you can buy one from HP. My only solution may be to purchase a new printer, which I don't want to do. Other than this problem, the printer has worked well up until now.