17. Malfunction code
Field Service Ver. 1.0 Jun. 2008
294
T
roubleshooting
C3721 Fusing abnormally high tem-
perature detection
(heating side)
• The heating roller thermistor continues to detect a
temperature higher than a predetermined one for a
predetermined period of time.
• Hard protection signal L is detected continuously
over a predetermined period of time.
A
C3723 Fusing abnormally high tem-
perature detection
(pressurizing side)
• The temperature of the pressure roller continues to
be higher than a predetermined level for a predeter-
mined period of time after a temperature correction.
A
C3821 Fusing abnormally low temper-
ature detection (heating side)
• The heating roller thermistor continues to detect a
temperature lower than a predetermined one for a
predetermined period of time.
• In the states other than a warm-up operation, a zero
cross signal cannot be detected after the lapse of a
predetermined period of time after the fusing heater
is turned ON or OFF.
• The power supply frequency cannot be detected.
A
C3823 Fusing abnormally low temper-
ature detection
(pressurizing side)
• The temperature of the pressure roller continues to
be lower than a predetermined level for a predeter-
mined period of time after a temperature correction.
A
C4151 Polygon motor rotation trouble
(C)
• The polygon motor fails to turn stably even after the
lapse of a given period of time after activating the
polygon motor.
• Motor lock signal detects HIGH for a given period
time consecutively during the polygon motor is rotat-
ing.
B
C4152 Polygon motor rotation trouble
(M)
B
C4153 Polygon motor rotation trouble
(Y)
B
C4154 Polygon motor rotation trouble
(K)
B
C4551 Laser malfunction (C)
• SOS signal is not detected even after the lapse of a
given period of time after staring the laser output.
• SOS signal is not detected for a given period of time
during printing or image stabilization adjustment.
B
C4552 Laser malfunction (M)
B
C4553 Laser malfunction (Y)
B
C4554 Laser malfunction (K)
B
C5102 Transport motor’s failure to
turn
• The motor lock signal remains HIGH for a predeter-
mined continuous period of time while the motor
remains stationary.
B
C5103 Transport motor’s
turning at abnormal timing
• The motor lock signal remains LOW for a predeter-
mined continuous period of time while the motor
remains stationary.
B
C5351 Power supply cooling fan
motor/1’s failure to turn
• The fan lock signal remains HIGH for a predeter-
mined continuous period of time while the motor
remains stationary.
B
C5354 Exhaust fan motor’s failure to
turn
• The fan lock signal remains HIGH for a predeter-
mined continuous period of time while the motor
remains stationary.
B
C5357 Cooling fan motor/1’s failure to
turn
• The fan lock signal remains HIGH for a predeter-
mined continuous period of time while the motor
remains stationary.
B
C6102 Drive system home sensor
malfunction
• The home position sensor (PS201) is defective or
the exposure unit operates erratically.
B
C6401 Other troubles of scanner
• The scan operation was terminated abnormally
because of a reason except defined trouble.
B
Code
Item
Detection timing
Rank
d-Color MF201
Service Manual Y109660-1
