HP 3840 - Manual (Page 14)

4.5 Ink-backup mode
In the ink-backup mode, the printer operates by using only one print cartridge. The
ink-backup mode is initiated when a print cartridge is removed from the print
cartridge cradle.
For instructions about removing 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 printouts.
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.
Note: It is recommended that you do not use the photo print cartridge for ink-
backup mode.
Exiting ink-backup mode
Install two print cartridges in the printer to exit ink-backup mode.
For instructions about installing a print cartridge, see the
print cartridge installation
page.
HP Deskjet 3840 series printer User's Guide
14