• Code: 551
• Description: Pressure roller thermistor error The temperature measured by the pressure roller thermistor does not reach 0°C for 120 seconds.
• Causes: • Loose connection of pressure roller thermistor • Defective pressure roller thermistor • Related SC code: SC 541, SC561
• Remedy: 1. Do SP5810 to cancel the SC fusing code. 2. Check that the pressure roller thermistor is firmly connected. 3. Replace the pressure roller thermistor.

• Code: 552
• Description: Pressure roller warm-up error 2 • The pressure roller temperature does not reach the ready temperature for 1600 seconds after the heating lamp on. • The pressure roller temperature does not reach 100°C for 700 seconds after the pressure roller lamp on.
• Causes: • Defective thermistor • Related SC code: SC 542, SC562
• Remedy: 1. Do SP5810 to cancel the SC fusing code. 2. Check if the pressure roller thermistor is firmly connected. 3. Replace the pressure roller thermistor.

• Code: 553
• Description: Pressure roller overheat (software error) The detected pressure roller temperature stays at 215°C or more for 10 seconds.
• Causes: • TRIAC short, AC drive board defective • Defective IOB 2 • Defective BCU • Related SC code: SC 543, SC563
• Remedy: 1. Do SP5810 to cancel the SC fusing code. 2. Replace the AC drive board. 3. Replace the IOB 2. 4. Replace the BCU.

• Code: 555
• Description: Pressure roller fusing lamp remains on After hot roller reaches warm-up temperature, the pressure roller fusing lamp remained for 360 sec. while the hot roller is not rotating.
• Causes: Thermistor damaged, or out of position
• Remedy: 1. Do SP5810 to cancel the SC fusing code. 2. Replace the pressure roller thermistor.

• Code: 557
• Description: Zero cross frequency error The detection error occurs twice or more in the 10 zero cross signal detections. This error is defined when the detected zero cross signal is less than 44.
• Causes: • Noise (High frequency)
• Remedy: Check the power supply source.

• Code: 558
• Description: Oil supply motor error The machine detects a motor rotation error for 5 seconds after the oil supply motor has rotated for 5 seconds.
• Causes: • Oil supply motor defective • Oil supply unit defective
• Remedy: 1. Replace the oil supply motor. 2. Replace the oil supply unit.

• Code: 559
• Description: 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").
• Causes: • Paper jam in the fusing unit.
• Remedy: 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.

• Code: 561
• Description: Heating roller thermistor error (end) The temperature measured by the heating roller thermistor does not reach 0°C after 45 sec. and remains over this temperature for 10 readings.
• Causes: • Loose connection of the heating roller thermistor • Defective heating roller thermistor
• Remedy: Replace the heating roller thermistor.