There could be a few reasons why your printer is not working. Try these troubleshooting activities: If the reactive side of the thermal paper is not facing the print head, reverse the printer paper. If the thermal paper is wet, clean and dry the inside of the printer housing and replace the printer paper. If the printer module is not connected, check the internal USB and power harness connection. If the printer does not have power, check J17 on the main board. If the printer module does not function, replace the printer module. If the USB cable is defective, replace the USB cable. If the power harness is defective, test the power harness. Replace if necessary. If no printer error is logged, the main board may be defective. Check the error logs for printer errors. Replace the main board if necessary. If the printer fuse has blown, check MCE printer fuse F5. Replace the MCE PCBA.