HP OfficeJet 8013 Printhead Cleaning - Missing Black or Color

--- For OfficeJet 8013 () degraded related and output (i.e. including or from or with your subscription, standard, aftermarket or refilled ink then it is first suggested to activate the 8013 printer&command from the printer’s menu. You may need to perform this action twice to help recover the printer. If this does not correct the print quality then it is suggested to remove all 4 cartridges from the carriage. You will want to inspect each cartridge for leaks and then re-install, verifying all cartridges properly lock into carriage assembly. If an quality issue persists then it is suggested to print a heavy colored or image to see if ink can be blown thru the internal printhead, and hopefully resume normal printing. Depending on which color is missing, create a document with either 100% black color blocks or 100% Cyan, Magenta or Yellow color blocks. Print the document 2-3 times back-to-back and check for normal print output. If each subsequent print starts to look better then the internal printhead may be recovering. However, if one color (or is not printing, such as the black ink, then the bottom of the PRINTHEAD may be clogged with dried or built up ink. It is suggested to open the printer and remove all 4 cartridges from the carriage assembly. Obtain several paper towels and fold 3 or 4 times, dampen with water. Place the damp towel into the lower tray area next to the carriage assembly; gently push the towel down to get it as flush with bottom as possible. Gently...