Examining The Nozzle Check Pattern - Epson Stylus Color 640 User Manual

Maintenance and Transportation
3 If your print quality has not improved, run another cleaning
cycle. If you don't notice any improvement after doing this three
or four times, see

Examining the Nozzle Check Pattern

Examine the nozzle check pattern after printing it. It should look
something like this:
Each staggered horizontal and straight vertical line should be
complete, with no gaps in the dot pattern. If your printout looks
okay, you're done. If any dots are missing, as shown below, clean
the print head again, as explained in the previous sections.
Improving Print Quality.
missing dots
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