If you own a Canon inkjet printer—particularly models from the PIXMA MG series, MX series, or the TS series—you have likely encountered the dreaded or "5B01" error code. This error usually indicates that the printer’s internal waste ink counter is full. For years, the only official solution was to take the printer to an authorized service center. However, advanced users and small repair shops have a secret weapon: The Canon Printer Service Tool V3600.