HP Deskjet 6122 Color Inkjet Printer - Manual (Page 92)

checking the print cartridge status
understanding the print cartridge status light
The Print Cartridge Status light flashes when one or both of the print cartridges are low
on ink, improperly installed, missing, or malfunctioning. This light also flashes if the
wrong print cartridge type is used.
1. print cartridge status light
If the ink level is low in a print cartridge, the Print Cartridge Status light stops flashing
when the printer's top cover is opened or the printer is printing. If the problem is not
related to low ink, the light continues to flash after the cover is opened.