• Code: SC543
• Description: Fusing overheat error 1 (software)
  A fusing temperature of over 215 °C (419°F) was detected for 5 s
• Causes: • IOB board defective • MCU board defective • PSU defective

• Code: SC544
• Description: Fusing overheat error 2 (hardware)
  The BICU detects an overhead error even if the software overheat protection does not work.
• Causes: • IOB board defective • MCU board defective • PSU board defective

• Code: SC545
• Description: Fusing lamp overheat error 3
  After reaching the ready temperature, the hot roller does not rotate, and the fusing lamp stays on at full power for 50 s.
• Causes: • Hot roller thermistor not positioned correctly

• Code: SC546
• Description: Unstable fusing temperature
  SC546-1 Fusing temperature rapidly fluctuating. Temperature fluctuates greater than 20°C (68°C) at 1 second intervals. SC546 -2 Fusing temperature fluctuating over a long interval. Temperature fluctuates 20°C (68°C) more than 3 times during 60 s interval.
• Causes: • Poor thermistor connection

• Code: SC547
• Description: Zero-cross signal malfunction
  SC547-1 Abnormal mains frequency was detected more than 10 times. SC547-2 No zero-cross signal detected for 1 second. SC547-3 No zero-cross signal detected for 2.5 s after the main switch is turned on.
• Causes: • Electrical noise on the power line. • PSU defective.

• Code: SC549
• Description: Pressure roller thermistor abnormal
  SC547-1 During fusing motor rotation, pressure roller temperature detected lower than 7°C (44.6°F) for 5 s. SC547-2 Pressure roller temperature detected higher than 235°C (455°F) for 5 s.
• Causes: • SC547-1: Thermistor disconnected or connector damaged. • SC547-2: Thermistor shorted or connector damaged.

• Code: SC550
• Description: Left fusing pressure motor home position error 1
  The left pressure motor did not return to home position 9 s after the left pressure motor started.
• Causes: • Motor drive mechanism overload. • Motor defective. • Pressure home position sensor defective.

• Code: SC551
• Description: Left fusing pressure motor home position error 2
  The left pressure motor was still at the home position 1.5 s after the start signal turned on.
• Causes: • Motor drive mechanism overloaded. • Motor defective. • Pressure home position sensor defective or disconnected.