Oki C821 Maintenance Manual

44015503TH Rev. 1
203 /
Oki Data CONFIDENTIAL
7. TROUBLESHOOTING PROCEDURE
Check item Check work
Action to be taken
at NG
(10-1-3) Sensor check
Up/Down sensor
lever (unified
structure with the
left link lever)
Chec
k if shape and movement of the sensor
levers have any abnormality or not.
Replace the left
link lever.
Up/Down sensor Confirm that the sensor signals are normally
detected by using the SWITCH SCAN function
of the self-diagnostic mode.
Check if the SCAN state changes or not when
the incoming light is interrupted/passed by using
a piece of paper or the like for the transparent
type sensor.
Replace the
high voltage
board.
(10-2) Error occurs during the Down movement of the ID unit
Check item Check work
Action to be taken
at NG
(10-2-1) Check the mechanical load during the Down movement
Mechanical load
during installation
and removal of the
ID unit
Check if abnormal heavy load is applied when
remo
ving the ID unit.
Replace the ID
unit, or replace
the right/left side
plate.
Greasing to the right
and left Up/Down
link levers
Check if the slant surface of the link lever is
coated by grease or not.
Apply grease.
Assembled
condition of the right
and left Up/Down
link levers
Chec
k if any part exists or not in the vicinity of
link lever, that hampers movement of the link
lever.
Assemble them
correctly.
7.5.2.(11) Fuser unit error (error 170 to 177)
(11-1) Error occurs immediately after the power is turned on.
Check item Check work
Action to be taken
at NG
(11-1-1) Thermistor is defective Note)
Upper thermistor,
lower thermistor,
frame thermistor
Check the respective thermistors if they are
shorted or opened internally.
Check the resistance value at the connector pins
in the bottom of the fuser unit.
(Refer to section 8.1 Resistance check (fuser
unit).)
Replace the
fuser unit.
If any attempt
of using new
fuser unit as
a trial is going
to be made,
be sure to use
the System
Maintenance
Menu FUSE
KEEP MODE.
Installed condition
of fuser unit.
Check if the fuser nit is pressed in until the
connector in the bottom of the fuser unit is surely
connected.
Re-set the fuser
unit.
Note! Service calls 171 error and 171 error can occur when the printer temperature is
below 0
˚C
. Turn on the power again after the printer temperature has increased.
(11-2) Error occurs approx. 1 minute after the power is turned on.
Check item Check work
Action to be taken
at NG
(11-2-1) Temperature increase of fuser unit
Thermostat,
halogen lamp
Heater of the fuser unit is controlled of its
temperature. Check if the fuser unit gets hot or
not by touching it with hands.
If the fuser unit temperature does not increase
and remains cold, check that the resistance
between pin-1 and pin-2, and that in between
pin-3 and pin-4 of the two connectors is in the
range of several ohms to several ten ohms
respectively. (Refer to section 8.1 Resistance
value (fuser unit).)
Replace the
fuser unit.
If any attempt
of using new
fuser unit as
a trial is going
to be made,
be sure to use
the System
Maintenance
Menu FUSE
KEEP MODE.

Oki C821 Specifications

General

Brand	Oki
Model	C821
Category	All in One Printer
Language	English