Ricoh B064 Service Manual page 373

SC No.
One of the following occurred:
• After power on, or after closing
the front door, the hot roller does
not reach the 100°C control
temperature within 25 s.
• 5 sec. after temperature rise
started, temperature remained
below 21°C after 5 samplings.
• Fusing unit did not attain reload
temperature within 48 sec. of the
start of fusing temperature
control.
543 A Fusing lamp overheat error 1 (software)
Central thermistor detected a
temperature of 240°C at the center
of the hot roller. Fusing temperature
control software error
544 A Fusing lamp overheat error 1 (hardware)
Either the central thermistor or an
end thermistor detected a
temperature of 250°C on the hot
roller.
-or-
Fusing temperature control
software error
545 A Fusing lamp overheat error 2
After hot roller reaches warmup
temperature, the fusing lamps
remained on at full capacity for 11
samplings (1.8 sec. duration) while
the hot roller was not rotating.
547 D Zero cross signal malfunction
One of the following conditions is
detected 10 times:
• When the main switch is on, the
frequency measured by the
number of zero cross signals for
500 ms is larger than 66Hz or
smaller than 45 Hz.
• The interval between one zero
cross signal and the next is 7.5
ms or shorter 3 times
consecutively for 500 ms.
550 A Fusing Web End
Web end detected 5 times within
500 ms and web motor continues to
rotate 40 s. If web end is detected
for another 400 ms, then the SC is
logged.
551 A Fusing thermistor error 1
SM
B140 SERIES AND G126 SERVICE MODE
Symptom
4-49
Possible Cause
• Fusing lamp disconnected
• Thermistor warped, out of position
• Thermostat not operating
• PSU defective
• IOB defective
• BICU defective
• PSU defective
• IOB defective
• BICU defective
• Thermistor damaged, or out of position
• Fusing lamp disconnected
• Noise on the ac power line
• Web end (requires replacement)
• Web end sensor defective
Note: After replacing the web with a new
one, reset SP1902 001 to 0 to
release SC550.
B064 Series/B140 Series/G126