FujiFilm Quality Dry Photo Paper for Frontier-S DX100 Printer (Glossy, 4" x 213' Roll, 2-Pack) - Manual (Page 46)

Checking Ink Levels
Checking from the Printer
When the ink remaining falls below the minimum value, the ink light on the front of the printer turns on.
U “Front” on page 6
Ink light
Checking from the Computer
Windows
A
Click Display Printer Status in the printer driver .
Frontier-S Operation Guide
Replacing Ink Cartridges
46