Hitachi UX Twin Nozzle Service Manual page 332

6.5.8b (N2) No ink ejection from nozzle2
Yes
Execute the "Nozzle
backwash2" function.
Yes
Is the problem
fixed?
No
Remove the orifice plate
from the nozzle, subject it
to ultrasonic cleaning, and
put it back on the nozzle.
Yes
Is the problem
fixed?
No
Does shutoff
valve MV29
operate?
No
Is there the conduction
of the fuse [FU19] of the
EZJ133 board?
No
Replace the
EZJ133 board.*1
Replace shutoff valve
MV29.
Yes
Is the problem
fixed?
No
Replace the circulation unit.
[Caution]
Resume the
1. Do not repeat the nozzle backwash procedure more than two times.
operation.
If it is repeated to an excess, the ink becomes thin, thereby causing
disordered prints.
2. If the ink is thin and printings become disordered, replace the ink.
No ink ejection
from nozzle2
Is ink pressure of
No
nozzle2 set to the value
specified?
Is the pump
motor running?
Is the Ink flowing
from the Ink filter "C"
motor running?
Replace the ink filter.
Yes Is the problem
fixed?
Is the Ink flowing from
the Reducing valve "C"
running?
Yes
Replace the pressure-
reducing valve.
Yes
Is the problem
fixed?
No
Is MV1 and 2
sticking?
Repair the troubled
solenoid.
Replace the MV1 and 2.
6-90
(*1): When you replace EZJ133 board, refer to
[Replacement
board] in "3.3.1 EZJ133 board (MPU
board)".
[Caution]
Be sure to check that there is no wrong
connection
[Connector numbers and Identifying method of
harnesses] in "3.3.20 Electrical Connection
No
Diagram".
Yes
Is the EZJ133 board
CN13 connector,
Yes
EZJ138 board CN1, 3,
4, and 6 connector, or
pump motor connector
No
disconnected?
No
Yes
No
Connect any
disconnected connector.
Yes
Is the problem
fixed?
No
No
Replace the
EZJ133 board.*1
Yes
Yes
Is the problem
fixed?
Replace the
circulation unit.
procedures of EZJ133
of harnesses by referring
No
Is the connection
harness conducting?
Yes
No
Replace the connection
harness.
Is the problem
fixed?
No
No
to
Yes
Yes