FujiFilm Quality Dry Photo Paper for Frontier-S DX100 Printer (Glossy, 4" x 213' Roll, 2-Pack) - Manual (Page 53)

Replacing the Maintenance Cartridge
The maintenance cartridge absorbs ink consumed during head cleaning.
This section explains how to replace used maintenance cartridges.
c Important:
After removing the maintenance cartridge, do not leave the cartridge cover open, install a new cartridge immediately.
Checking the Free Space in the Maintenance Cartridge
Checking from the Printer
When it is time to replace the maintenance cartridge, the printer's light turns on.
U “Lights” on page 11
light
Frontier-S Operation Guide
Replacing the Maintenance Cartridge
53