HP K550 blak print failure

Try uninstalling your PDF program, reboot and reinstall the latest version. It may be the way it is parsing the colours, if the Printer Test Page printed okay.

If you have tried a new toner cartridge and that didn't fix it you probably need to put in a new drum or Fuser kit. If it is really old and has had a lot of use I would consider replacing the whole printer with a new one. The fuser kit I saw listed on Amazon for this printer was half the price of a newer printer. If you do a lot of printing or this is in a business environment make sure when looking at replacements that you get one rated for the number of pages you print a month. I have had really good luck with HP and Brother laser printers.

your printer ink heads may need to be reset/relined.

When was the last time you printed in color? New ink printers are built so with a "use it or lose it" theme. The print heads are now built into the machines and are not generally replaceable. Yours luckily is, but I don't know how easily. The link below is to the replacement which costs $130 + shipping. Sometimes it can be just as worth it to buy a new machine, in this case I would probably prefer to repair the damaged machine as the new printer cartridges cost more and have less ink.

Print a few pages. As they are printing open the cover. Remove the toner cartridge. Look down at the page that was being printed. If it is not "streaky" look at the fuser, it probably needs replacing.

If that page is "streaky" replace the toner cartridge.

Sounds like the printhead is plugged on the black side. A new printhead is #qy6-0052-000 around $40.00. That model also needs a firmware update to help it clean the printhead better.

your printer heads is built-in in your cartridge.... if that printer prints wrong colors your using refill ink....

Had the same problem for weeks. Had to go thru all three levels of print head cleaning in the HP Toolbox menu to get black to work again. The head cleaning option on the printer itself was insufficient. Unless you've already gone thru all three cleaning levels this may be worth a try.

I walked thru the steps via the HP website FAQs for the 6180. Basically: Open the HP Solution Center, select Settings->Print Settings->Printer Toolbox, then click Clean the Printheads. After the first cleaning you'll be asked if the test page printed OK (mine didn't), click the Intermediate Cleaning box. You'll be asked again if the test page printed OK (mine did, but an independent MSWord print test was still streaky), click the clean again (sorry, don't remember what this one was called) for the third and deepest clean.

This last one worked for me, now it's back to normal printing. From what the HP website says I'm guessing that my black print head was dried up. That's a reasonable explanation for my situation, we had let the black sit dormant for a couple of weeks after the black cartridge ran out before we tried to install a replacement.

Hope this helps, sure was frustrating for me. Good luck.

Hi drglass1 -

13,000 copies - that's awesome! although you've surely fixed this problem by now, for future refs or someone else searching for an answer... you might find this ref hp support helpful. happy printing!

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00458018&lc=en&dlc=en&cc=us&lang=en&rule=35557&product=501369

Step 4: Clean the printheads
If the print quality is still bad, clean the printheads:
1. Make sure the printer is loaded with unused white paper.
2. Open the printer Toolbox and select the Printer Services tab.
3. Click Clean Printheads . A Clean Printheads window opens. Click Level 1 Clean .
4. Examine the page that prints for print defects.
a. If there are no defects, click Exit . Stop troubleshooting here .
b. If there are defects on the page, click Level 2 Clean . 5. Examine the page that prints for print defects.
a. If there are no defects, click Exit . Stop troubleshooting here .
b. If there are defects on the page, click Level 3 Clean . Note that Level 3 cleaning uses a lot of ink – it is not recommended if the cartridges are low on ink. - JW50

First with a clean soft cloth and a very small amt of alcohol clean off the underside of the printer carridge (the holder for the print heads) also where the print heads cleaning station is clean out any large masses of congealed link. Then remove the ink cartridge in question and with a pencil eraser gently rub the contacts and both the cartridge and the carridge replace the cartridge. Using the software tools for the printer clean and align the printheads ( if there is an option to do so). If this dosn't fix the problem try a different ink cartridge.