44952001TH Rev.2
7-75
Oki Data CONFIDENTIAL
7. TROUBLESHOOTING PROCEDURES
7.5.5. (11) Fuser unit error (error 170 to 177)
(11-1) Error occurs immediately after the power is turned on.
Check item
Checking method
Action in case of 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 . 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
Checking method
Action in case of 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.
Check item
Checking method
Action in case of NG
(11-2-2) Temperature increase of fuser unit
Installation position
of the upper
thermistor
Check if the upper thermistor is installed in
the far position from the specified position
or not causing detection of the lower
temperature than the actual temperature of
fuser unit.
Remove the heater cover, and check
warpage of sensor by visual inspection.
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.
Installation position
of the lower
thermistor
The lower thermister must be installed
while contacting with the fuser unit. Check
if the lower thermister is installed in the far
position from the specified position or not
causing detection of the lower temperature
than the actual temperature of 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.
(11-2-3) AC power input to the halogen lamp
AC power voltage
from the low voltage
power supply
Check if the AC voltage for heater is
normally supplied or not.
Power supply CN2 connector , between
pin-1 and pin-2, and between pin-3 and pin-4.
Replace the low
voltage power supply.
Heater ON signal
that is output from
CU/PU to the low
voltage power supply
Check that the heater ON signal goes active
at the warming up timing, or not.
"L" active while ON.
CU/PU board POWER connector
⑩
pins 14
and 15
Replace the CU/PU
board.
