The Epson PX660 has a finite internal counter that tracks how many cleaning cycles, power-on events, and borderless prints you have performed. Each of these actions pumps a small amount of ink into a sponge pad inside the printer. Epson’s firmware is designed to stop the printer entirely (Error: 0x9A or 0x9B) after approximately 15,000 to 20,000 pages or 5,000 cleaning cycles, regardless of whether the pad is actually full. The adjustment program tells the printer to forget this count.
The flashing red lights on the PX660 are essentially the printer saying, "I am full, and I need service."