¶ 1. Turn off the machine and unplug the power cord.
¶ 2. Use an Allen wrench to remove the fixing screws on both sides of the nozzle cover.
¶ 3. Remove the nozzle cover and disconnect the model cooling fan connector.
¶ 4. Using a hex key, remove the three pan head screws that secure the nozzle sub-plate.
¶ 5. Separate the motor wire connector terminal, the ceramic heating ring wire connector terminal, and the thermistor wire connector terminal located on the back of the print head's small board, as well as the small board's data transmission line terminal.
¶ 6. Remove the cooling fan terminal from the old nozzle sub-board, insert the terminal into the slot of the new nozzle sub-board so that the fan nameplate faces away from the nozzle sub-board and aligns with the fan mounting holes. Insert the three pan head screws that secure the nozzle sub-board through the mounting holes of the nozzle sub-board and the cooling fan.
¶ 7. Connect the motor wire connector, ceramic heater ring wire connector, thermistor wire connector, and the small board data transfer wire connector to the corresponding terminal slots on the small board. Then, using an Allen wrench, tighten the three nozzle small board fixing screws.
¶ 8. Verify that the terminal positions on the printhead sub-board are correctly oriented and installed, and that the terminals are properly snapped into the slot holders.
¶ 9. Lift the nozzle cover, insert the model cooling fan terminal into the corresponding terminal slot on the front of the nozzle sub-board, secure the fan cover, and tighten the left and right fan cover fixing screws.
¶ 10. Nozzle sub-board replacement completed.
