Service manual

31
Long test mode
If the printer is turned on while the PAPER FEED button is pressed, the
printer will enter the long self-mode. The printer will print the version number
of the printer’s ROM, the current Electronic DIP Switch (EDS) settings and
the current Dot Adjustment settings, followed by the entire character set
printed in each font and pitch available.
The test repeats endlessly, so you must turn the power off to stop it.
Figure 4-4. Long self-test.
Since the self-test prints across the full width of the carriage, it is recommended
that the printer is loaded with the widest paper possible to avoid damage to
the print head and/or platen. In addition, the total number of lines printed is
considerable, more than can be accommodated on a single sheet, so fanfold
paper is recommended for this test.