Ricoh MP C307 Field Service Manual page 449

SC5xx: Paper Feed and Fusing
No. Type
2.
No. Type
SC549-00 D Fusing Center Low Temperature
After passing 60 seconds when FGATE is ON, thermopile detects a temperature of -100
degrees C from the compensated target temperature for consecutive 60 seconds.
•
•
1.
2.
3.
4.
5.
No. Type
SC554-00 A Fusing thermistor (NC sensor) detects high temperature (Hard)
Fusing thermistor (NC sensor) detects a temperature of 250 degrees C..
•
•
•
Basically, the entire fusing unit must be replaced when SC554-00 occurs. For details, refer to
"Actions When SC544-00 or SC554-00
Do the following steps:
1.
2.
3.
4.
5.
6.
No. Type
SC557-00 C Zero cross frequency error
The frequency of the power source is 66Hz or more. This SC is detected just after the main
power is turned ON.
•
•
1. Check the power supply source.
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Replace the PSU (AC).
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Fusing lamp disconnection during paper passing
Loose connector
Check the input voltage and reconnect the power cord.
Replace the fusing lamp.
Replace the fusing thermopile
Replace the BiCU.
Replace the PSU (AC).
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Shorted triac
Defective BiCU
Defective fusing control system
Inspect the fusing sleeve belt unit, and replace if damaged.
Reconnect the connector between the fusing unit and the BiCU.
Replace the fusing thermistor.
Replace the harness between the fusing unit and the BiCU.
Replace the BiCU.
Replace the PSU (AC).
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Noise (High frequency)
Defective PSU
Occurs."
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