Ricoh G188 Service Manual page 328

Service Call Conditions
No. Type
Zero cross frequency error
When the zero cross signal is 66 or more and it is detected 10 times or
more in 11 detections, the machine determines that input 60 Hz and
SC557 occurs.
557 C
1.
2.
No. Type
Consecutive fusing jam
The paper jam counter for the fusing unit reaches 3 times. The paper
jam counter is cleared if the paper is fed correctly.
This SC is activated only when SP1159-001 is set to "1" (default "0").
559 A
Remove the paper that is jammed in the fusing unit. Then make sure
that the fusing unit is clean and has no obstacles in the paper feed path.
No. Type
Pressure roller thermistor error
The temperature detected by the pressure roller thermistor does not
reach 0 °C for 37 seconds.
561 A
1.
2.
G188/G189
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Noise (High frequency)
Defective PSU
Check the power supply source.
Replace the PSU.
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Paper jam in the fusing unit.
Details (Symptom, Possible Cause, Troubleshooting Procedures)
Loose connection of the pressure roller thermistor
Defective pressure roller thermistor
Check if the pressure roller thermistor is firmly connected.
Replace the pressure roller thermistor.
3-32 SM Appendix