Oki B721 Maintenance Manual

Oki Data CONFIDENTIAL
45487001TH Rev.1
6-64 /
6. Troubleshooting procedure
6.5.2.(17) Humidity sensor error (Error 123)
(17-1) Humidity sensor error
Check item Check work
Actions to be taken
at NG
(17-1-1) Check the system connection
Connection
between the PU/
CU board and the
control panel board
Check if the 10-conductor FFC is connected
to the OPE connector
of the PU/CU board
properly.
Check if the 10-conductor FFC is connected
to the CN501 connector
of the control
panel board properly.
Check the connectors for half-way connection
or angled connection.
Re-connect the
cable normally.
FFC connecting the
PU/CU board and
the control panel
board
Check for open-circuit with VOM.
Visually check that the sheath for peeling.
Replace the
FFC with a
normal FFC.
FFC connecting the
PU/CU board and
the environment
sensor board
Check for open-circuit with VOM.
Visually check that the sheath for peeling.
Replace the
FFC with a
normal FFC.
Check item Check work
Actions to be taken
at NG
(17-1-2) Environment condition
Sharp change
of environment
condition
Is the environment condition changed sharply
from a low temperature environment to a high
environment condition within a short time?
(Example is such a case that a printer is
moved from storage condition of a cold area
in winter to an office environment.)
Leave a printer
for around one
hour in the new
environment
to get used
to the new
environment.
After that, turn
on the power
again.
Before turn
on the power,
touch the metal
panel of the
controller panel
and the metal
plate inside a
printer to feel
temperature
increase
inside a printer
with human
hands. After
confirmation
that the printer
temperature has
increased close
to the room
temperature,
turn on the
power again.

Oki B721 Specifications

General

Print Technology	LED
Resolution	1200 x 1200 dpi
Processor	533 MHz
Memory	256 MB
Connectivity	USB, Ethernet
Duplex Printing	Standard