Hitachi IJ UX Service Manual page 269

6.4.13 Ink Pressure Low
Ink Pressure Low
Yes
Does MV1, 2, 4, 9 operate?
Replace or repair the troubled
solenoid.
Does ink flow into main ink tank
when operating pump, MV1 &
MV6?
No
Replace or repair the
supply pump
Can the pressure be adjusted by
the pressure reducing valve?
Yes
Adjust the pressure to standard value
by the pressure reducing valve.
Is the warning released?
Resume the operation.
No
Yes
Yes
No
Yes
Yes
Yes
No
Yes
6-51
Does ink flow into main tank when
operating pump, MV2 & MV6?
No
Replace or repair the CV assembly.
Replace the three-way valve filter.
Can the pressure be adjusted by
the pressure reducing valve?
No
Replace the viscometer filter.
Can the pressure be adjusted by
the pressure reducing valve?
No
Replace the pressure reducing valve.
Can the pressure be adjusted by
the pressure reducing valve?
No
Replace the pressure sensor.