The tool provides access to "Service Mode" functions that are generally unavailable through standard printer drivers.
PIXMA Pro-10, Pro-100, Maxify 5350, and various G-series MegaTank printers. canon service tool v5204
Often works with printers using PGI-550/CLI-551 through PGI-580/CLI-581 cartridge generations. The tool provides access to "Service Mode" functions