• Code: 553
• Description: Fusing overheat error 1 (software detection)
  A fusing temperature (at the end) of over 230°C (446°F) is detected for 1 second by the fusing thermistors at the center or at either end of the fusing roller.
• Causes: • Power supply unit defective • I/O board (IOB) defective • BICU defective • TRIAC short on PSU (PSU defective)

• Code: 554
• Description: Fusing overheat error 1 (hardware detection)
  A fusing temperature (at the end) over 250°C is detected by the fusing temperature monitor circuit in the BICU board.
• Causes: • I/O board (IOB) defective • BICU defective

• Code: 555
• Description: Fusing lamp consecutive full power 1
  After warm-up, the fusing lamp remains at full power for 15 seconds without the hot roller rotating.
• Causes: • Disconnected or defective thermistors (ends) • Defective fusing lamp

• Code: 557
• Description: 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.
• Causes: • Noise (High frequency)

• Code: 559
• Description: Fusing unit jam
  The fusing sensor detected a fusing unit paper late jam three times. The paper was late and the fusing exit sensor could not detect the paper three times.
• Causes: • Remove the paper that is stopped in the fusing unit. • Check that the fusing unit is clean and has no obstacles in the paper feed path. • If the error persists, replace the fusing unit.

• Code: 610
• Description: Mechanical counter error: BK
  This SC is only for NA models. The machine detects the mechanical counter error when SP5987-001 is set to 1
• Causes: • Disconnected mechanical counter • Defective mechanical counter

• Code: 621
• Description: Communication timeout error between IOB and finisher or mailbox
  A break (low) signal is received from the finisher or the mailbox.
• Causes: • Disconnected cable • Defective IOB • Defective main board in the peripherals

• Code: 622
• Description: Paper feed unit communication error
  While the IOB communicates with a peripheral, an SC code is displayed if one of following conditions occurs. • The IOB receives the break signal which is generated by the peripheral only just after the main switch is turned on. • The IOB receives the break signal which is generated by URAT.
• Causes: • Defective main control board of the peripheral • Defective BCU or IOB • Disconnected peripheral