Ricoh D131 Service Manual page 499

SC500: Feed, Transport, Duplex, and Fusing
SC544 A
SC545 A
SC547-01 D
SC547-02 D
D131/D132/D133
Fusing lamp overheat error 1: Hardware
The center thermistor or an end thermistor detected a temperature
of 250°C on the hot roller.

PSU defective

IOB defective

BICU defective
Fusing lamp overheat error 2: Center lamp
After hot roller reaches warm-up temperature, the fusing lamps
remained on at full capacity for 11 samplings (1.8 s. duration) while
the hot roller was not rotating.

Thermistor damaged, or out of position

Fusing lamp disconnected
Zero cross signal error 1: Fusing relay
At power on and with the fusing relay off, 3 samplings detected that
the zero cross was not normal.

Fusing relay short

Fusing relay drive circuit defective
Zero cross signal error 2: Fusing relay
No zero cross signal was detected within 3 sec. after power on or
after closing the front door.

Fusing relay short

Fusing relay drive circuit defective
2-32 SM Appendix