Load A4 -size plain paper in the printer.
Select on the printer's control panel.
Select Maintenance.
Select Print Head Cleaning > Power Cleaning.
When cleaning is finished, print the nozzle check pattern again. Check that all of the lines in the nozzle check pattern are printed correctly.
If print quality has not improved after running Power Cleaning, wait for at least 6 hours without printing, and then print the nozzle check pattern again. Run Head Cleaning or Power Cleaning again depending on the printed pattern. If quality still does not improve, contact Epson support.