Hitachi UX Twin Nozzle Service Manual page 336

6.5.12 Increase of dot missing
- "Dot missing" is the phenomenon in which some of
the dots comprising a character are lost.
Generally, one dot missing per several thousand
dots may occur in the normal situations, but this
dot missing may increase if the abnormal state
as follows are continued:
(1) IJ printer was left in the state that the ink was not ejected due to nozzle clogging,
even though the printer was in "Standby" state.
(2) Ink is contaminated by moisture, dust or other foreign matters.
If dot missing increases, perform the following troubleshooting, referring to the Technical
Manual:
(1) Replace the ink filter (Refer to "Technical Manual 6.6 Replacing the ink filter").
(2) Replace the ink (Refer to "Technical Manual 6.2 Replacing the ink").
Deflecting
direction
6-94
Dot
missing