Oki B721 Maintenance Manual page 161

Oki Data CONFIDENTIAL
Panel display Cause
Service Call An unexcepted error
254: Error occurred during
initializing the
security mode. Error
cause information
was displayed after
an error number.
Service Call An unexcepted error
257: Error occurred during
initializing HDD.
HDD Error cause
information was
displayed after an
error number.
Power Off/On Short or open in
901: Error, 902: Internal thermistor
Error detected.
Power Off/On Abnormal
903: Error, 904: temperature
Error detected by Internal
thermistor
(high-temp or low
temp.)
Power Off/On The Geared Motor
911: Error, 912: Error at the Optional
Error Tray.
911:Tray2
912 Tray3
45487001TH Rev.1
Check details Result Solution
Power Off/On.
Does error reoccur? Yes Regenerate an
encryption key. If it
doesn't solve the
problem, replace
the PU/CU board
or encrypted HDD.
Power Off/On.
Does error reoccur? Yes Format the HDD
again. If it does not
solve the problem,
replace the HDD.
Is internal thermistor No Connect cable set
cable setting proper? properly again.
Yes Turn power ON
again.
Does error reoccur? Yes Replace the
internal thermistor.
Is internal thermistor No Connect cable set
cable setting proper? properly again.
Yes Turn power ON
again.
Does error reoccur? Yes Replace the
internal thermistor
and leave aside for
30 minutes.
Then turn power
ON again.
Is the indicated tray No Install the optional
installed properly? tray properly.
Yes Turn power ON
again.
Does error reoccur? Yes Replace the
Geared Motor of
indicated tray.
Panel display Cause
Power Off/On An error was
918: Error detected with the
Duplex Fan Motor.
Power Off/On An error was
923: Error detected with the
image drum motor
by overload.
Power Off/On An error was
928: Error detected the Fuser
Motor rotation by
overload.
Power Off/On Tray2 CPU Clock
933: Error Frequency Error
Power Off/On Tray3 CPU Clock
934: Error Frequency Error
Power Off/On Tray4 CPU Clock
935: Error Frequency Error
Power Off/On A watch dog timer
941: Error error was detected.
Power Off/On An undefined
942: Error interruption was
detected.
6. Troubleshooting procedure
Check details Solution
Result
Power Off/On.
Does error reoccur? Yes Check if the FAN
is connected
properly.
Does error reoccur Yes Replace the FAN.
after power restoration?
Check if the image
drum is installed
properly.
Does error reoccur Yes Replace the image
after power restoration? drum unit.
Does error reoccur Yes Replace the ID
after power restoration? motor.
Check if the
fuser is installed
properly.
Does error reoccur Yes Replace the fuser.
after power restoration?
Does error reoccur Yes Replace the fuser
after power restoration? motor.
Does error reoccur Yes Replace the unit.
after power restoration?
Does error reoccur Yes Replace the PU/
after power restoration? CU board.
Does error reoccur Yes Replace the unit.
after power restoration?
Does error reoccur Yes Replace the PU/
after power restoration? CU board.
Does error reoccur Yes Replace the unit.
after power restoration?
Does error reoccur Yes Replace the PU/
after power restoration? CU board.
Power Off/On.
Does error reoccur? Yes Replace the PU/
CU board.
Power Off/On.
Does error reoccur? Yes Replace the PU/
CU board.
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