Epson TM-C3400 Technical Reference Manual page 106

Void image test print
Perform a test print of the image to print when dot missing occurs in the High Reliability Mode
(Void Image Print).
1
Turn the printer on.
2
Display the printer driver window.
(See How to Use the Printer Driver on page 154
3
Select the [Maintenance And Utilities] tab and click [Missing Dot Opera-
tion].
4
Select [Void Image Test Print] and click [Next].
5
Click [Test Print] to start test print.
Click [Cancel] to terminate without performing test print.
106
for how to display the driver window.)