Oki C3200n, Service Manual

Page: 189 / 262

Oki Data CONFIDENTIAL
42615101TH Rev.8
189 /
7.5.2.(1) LCD Display Malfunction
(1-1)Nothing is displayed in LCD
FU6 (Fuse) of PU board
(PRN PCB)
Connecting the low voltage
power unit with a PU board
(PRN PCB)
Cord-Assembly connecting
the low voltage power unit
with a PU board (PRN PCB)
Connecting a PU board
(PRN PCB) with an operation
panel board (PRP PCB)
FFC connecting a PU board
(PRN PCB) with an Operation
panel board (PRP PCB)
Operation Panel Board
(PRP PCB)
AC Power which is offered to
the printer
The voltage setting of the low
voltage power unit
(100V series /230V series)
5V Power which is offered to
a PU board (PRN PCB)
5V Power which is offered to an
operation panel board (PRP PCB)
5V power, 3.3V power and
24V power which are offered
to a PU board (PRN PCB)
Confirmation Tasks
Confirm that FU6 is not cut.
Confirm that a cord is correctly connected to POWER connector
of the PU board (PRN PCB) from the low voltage power.
Check half connection or incomplete plug-in.
Check if it is disconnected.
Confirm that the cover is not removed.
Confirm cord assembly defects such as a lack of line materials.
Confirm that a line material supports the connection1pin-1pin.
Confirm that 9-pole FFC is correctly connected to OPE
connector of the PU board (PRN PCB).
Confirm that 9-pole FFC is correctly connected to CN connector
of the PU board (PRN PCB).
Check half connection or incomplete plug-in.
Check a disconnection with a tester. Confirm that the cover is
not removed by eyes.
Confirm whether to use a board of C5300/5100 (RSP PCB) for
the operation panel board.
Check Supply voltage of AC power.
The measurement of the supplied AC voltage.
Check the power setting of the device being used.
(Check a short plug for change of the low voltage setting. Short
plug with/ without=100V series/ 230V series)
Check 5V with POWER connector 7,8,9pin of PU board (PRN
PCB).
Check 5V with CN connector 4pin of the operation panel board
(PRP PCB).
Confirm a short with POWER connector of PU board.
4,5,6pin:24V
7,8,9pin:5V
10,11,12pin:3.3V
13,14,15,16,17pin:0VL
1,2,3pin:0VP
For the above, classify location where a short occurs. Identify a
short location by plugging off cords connected to PU board
(PRN PCB) one by one.
Action at NG
Change FU6 or
PRN PCB.
Plug in the cord
correctly.
Change it to the correct
cord.
Plug in the cord
correctly.
Change to a normal
FFC.
Change to C5400/5200
board.
Supply AC power.
Adjust the low voltage
power setting.
Change of the low
voltage power.
Change to FU6 or
PRN PCB.
Change the part of the
short.
Confirmation Items
(1-1-1)Confirm fuse
(1-1-2)Confirm connection systems
(1-1-3)Confirm the power systems
(1-1-4)Confirm the power short