Accuracy of Printhead Health status from Print Quality Test

[MrsKG]

I've done an extensive search regarding this problem.  The HP L7780, which functioned well for years, suddenly prints everything in PINK.  All attempts to clean, realign etc, etc fails to correct the problem.  I'm left to accept that the print heads, one or both are potentially faulty.

However, I'm confused because the Print Quality Test reports that the health of both print heads are "GOOD".  Before I invest $90/each for two new printheads I would like to know if the Print Quality Test can give a false positive?  

Has anyone encountered a situation where new printheads remedied the problem even thought the Print Quality Test indicated the previous printheads were GOOD?  How reliable are the printer's diagnostics when it comes to reporting the printhead health?

[Rainbow23]

@MrsKG,

Welcome to HP Forums, this is a great place to get support, find answers and tips.

Thank you for posting your query, I'll be more than glad to help you.

I understand that you are facing print quality issues with your HP Officejet Pro L7780 All-in-One Printer.

This issue could occur if the nozzles of the printhead are clogged or it could be a hardware issue with the unit.

Let's go through a few steps to resolve this issue.

And here's the step by step guide for you in the link: Fixing Print Quality Problems

Since the print quality diagnostic report says that the printhead health is good, it could be an issue with the ink tubes connecting the cartridge and the printhead.

Let me know how this works.
 

You have a good day ahead.
 

[MrsKG]

Thanks for your prompt reply.  As I mentioned I had already researched the problem and tried the possible solutions suggested on the HP site and in their videos.  None of these provided a remedy.  Today I uninstalled all of the printer software and then ran the Level 4 cleanup BAT file from the original HP CD.  From an mechanical and connectivity point the printer and is working correctly.  But the print quality continues to be extremely poor. I've tried all of the steps recommended.  I also soaked the printheads in warm water for a short time.  All four colors released from the printhead during soak but neither the yellow or cyan pass through to the printer.  How can I determine if the ink tubes are blocked? I ask again, are the printheads faulty even though the quality reports say "GOOD"?

[The_Fossette]

Hi @MrsKG

Thank you for posting back.

I am the The_Fossette. It looks like you were interacting with @Rainbow23, but he is out of the office today so I'll take over from here.

If you have followed all the steps provided in the link in the previous post, then I recommend you to replace the printhead and check.

You may also contact phone to check the available service options for your printer.

Follow below steps to contact phone support.

Step 1. Open link:  www.hp.com/contacthp/
Step 2. Enter Product number or select to auto detect
Step 3. Scroll down to "Still need help? Complete the form to select your contact options"
Step 4. Scroll down and click on HP contact options - click on Get phone number

Take care.

Cheers!

[MrsKG]

Thanks for replying. 

It would be a relief to replace the printheads if I felt very certain that would corrrect the problem.  My hesistation is paying that amount of money only to learn the print quality does not improve.  I already wasted money on a new yellow cartridge (thinking that was the problem) I really don't want to throw more good money after bad.  I wish I knew for certain the root cause was indeed faulty printheads.  Why is the report showing their health as "GOOD"?

I used the Print & Scan Doctor.  It confirmed the printer was setup correctly.  The cyan still comes and goes and the yellow is completely absent from the print report.  I took another look at the print tubes to ensure they're not kinked and noticed air bubbles in the yellow line. How can I purge the ink tubes to remove the air?  What function does "calibrate feedline" actually performed?  Does it purge the ink tube lines? 

At this point I'm willing to try anything- it's already broken.

[The_Fossette]

Hi @MrsKG

Thank you for posting back.

I really appreciate your time and efforts.

I will not be able to tell you that replacing the printhead will certainly resolve the print quality issue. As you have already replaced the cartridge the next step will be to replace the printhead and check.

I recommend you to contact phone support and check the available upgrade options for your printer.

Follow below steps to contact phone support.

Step 1. Open link:  www.hp.com/contacthp/
Step 2. Enter Product number or select to auto detect
Step 3. Scroll down to "Still need help? Complete the form to select your contact options"
Step 4. Scroll down and click on HP contact options - click on Get phone number

Take care.

Cheers!