Epson WF-3520-3521-3522 Error 0x9 D The Epson WF-3520-3521-3522 printer may show an error code 0x9 D with a display on the printer, indicating various issues related to printer head failure. These issues can range from X-Hot detection error during flushing to abnormalities detected by the head thermistor and even main board failure. One possible cause…