HP Deskjet 6840 Color Inkjet Printer - Manual (Page 15)

1. Selection number label
• Printer documentation: For a list of print cartridge selection numbers, see the
reference guide that came with the printer.
• HP Inkjet Toolbox: Open the HP Inkjet Toolbox , and then select the Supplies
panel.
If a print cartridge runs out of ink, the printer can operate in the
ink-backup mode .
For information about installing a print cartridge, see the print cartridge installation
page.
4.7 Ink-backup mode
In the ink-backup mode, the printer operates by using only one print cartridge. The
ink back-up mode is initiated when a print cartridge is removed from the print
cartridge cradle.
To remove a print cartridge, see the
print cartridge installation page.
Ink-backup mode output
Printing in ink-backup mode slows the printer and affects the quality of printed
documents.
Installed print cartridge Result
Black print cartridge. Colors are printed as grayscale.
Tri-color print cartridge. Colors print but black is grayed and is not a true black.
Photo print cartridge. Colors are printed as grayscale.
Gray photo print cartridge. Colors are printed as grayscale.
HP Deskjet 6800 series printer User's Guide
15