Kyocera FS-9120DN Service Manual page 6

FS-9120DN/9520DN
Code
Abnormally low fuser unit thermistor
6050
temperature
• When only fuser heater M is on, fuser
unit thermistor 2 detects temperature
lower than 80 °C/176 °F during print-
ing.
• When fuser heater M and fuser unit
heater S are on, fuser unit thermistor
2 detects temperature lower than 80
°C/176 °F or fuser unit thermistor 1
detects temperature lower than 100
°C/212 °F during ptinting.
• The detection history of "6050" is
stored. If "6050" is detected several
times continuously, when the power
switch is turned on next, "6050" is im-
mediately displayed and the machine
stops.
(Method of clearing: See P.1-5-15.)
Zero-crossing signal problem
6400
• The engine controller PWB does not
detect the zero-crossing signal (Z
CROSS SIG) for the time specified
below.
At power-on: 5 s
Others: 5 s
Fuser unit connector insertion prob-
6410
lem
• Absence of the fuser unit is detected.
Fuser unit fuse cut problem
6420
• When you try to cut the fuser fuse,
the fuse is not cut even after 3 s
elapse.
Toner sensor problem
7300
• While the toner container sensor is
on, the toner sensor in the developing
unit does not turn on after the toner
sensor turns off and toner is replen-
ished from the toner container.
1-5-22
Contents
Causes Check procedures/corrective measures
Broken fuser Check for continuity. If none, replace the
heater M or S fuser heater M or S (see page 1-6-20).
wire.
Poor contact in Check the connection of connectors YC1-3
the connector ter- on the engine controller PWB and YC2-6
minals. on the power supply unit, and the continu-
ity across the connector terminals. Repair
or replace if necessary.
Defective power Check if the zero-crossing signal is output
supply unit. from YC2-6 on the power supply unit. If
not, replace the power supply unit.
Defective engine Replace the engine controller PWB if
controller PWB. C6400 is detected while YC2-6 on the
power supply unit outputs the zero-cross-
ing signal.
Fuser unit con- Reinsert the fuser unit connector if neces-
nector inserted sary.
incorrectly.
Defective fuser Replace the fuser unit.
unit connector.
Poor contact in Check the connection of connector YC10
the connector ter- on the engine controller PWB and the con-
minals. tinuity across the connector terminals. Re-
pair or replace if necessary.
Fuser unit con- Reinsert the fuser unit connector if neces-
nector inserted sary.
incorrectly.
Defective toner Replace the toner sensor.
sensor.
Poor contact in Reinsert the connector. Also check for con-
the toner sensor tinuity within the connector cable. If none,
connector termi- remedy or replace the cable.
nals.
Defective toner Replace the toner container sensor.
container sensor.
Defective toner
Replace the toner container.
container.
Remarks