This is for the HP 600 series printers pen cleaning process.

FROM THE CONTROL PANEL
With the printer on, press and hold the Power button while pressing the Resume button seven (7) times. Then release the Power button.

Note
The cleaning routine of spitting ink and printing uses ink. Therefore, avoid excessive use of the cleaning routine to maximize the print cartridge life.

IDENTIFYING A SUCCESSFUL CLEANING
To verify a successful cleaning routine, first inspect the nozzle pattern (diagonal line) at the top of the page. If you see a gap in the line, one or more dots are clogged in the print cartridge that produced the line.

Now, inspect the bottom diagonal line. If the gap present in the line at the top of the page is not repeated in the diagonal line at the bottom of the page, the cleaning routine (which produced the bands in the middle of the page) was successful. If the gap is repeated in the bottom line, repeat the test. If the gap is still present, replace the cartridge