• Code: 544-00
• Description: Fusing thermopile overheat (hardware error) The fusing thermopile detects a temperature of 250 degrees C.
• Causes: • Defective BiCU • Defective fusing control system
• Remedy: Related SC code: SC 543 1. Replace the BiCU.

• Code: 545-01
• Description: Fusing lamp consecutive full power The fusing lamp runs at full power for consecutive four seconds after reloading he machine
• Causes: • Defective thermistor • Broken heater • Thermostat blown out
• Remedy: 1. Check there is paper remaining in the fusing unit. 2. Replace the power cord. 3. Replace the fusing thermostat. 4. Replace the fusing lamp. 5. Replace the fusing thermopile. 6. Replace the AC controller board, or the BiCU.

• Code: 545-11
• Description: Fusing lamp consecutive full power (low power) The fusing lamp runs at full power for consecutive four seconds after reloading the machine
• Causes: • Defective thermistor • Broken heater • Thermostat blown out.
• Remedy: 1. Check there is paper remaining in the fusing unit. 2. Replace the power cord. 3. Replace the fusing thermostat. 4. Replace the fusing lamp. 5. Replace the fusing thermopile. 6. Replace the AC controller board, or the BiCU.

• Code: 547-01
• Description: Zero cross error: fusing lamp relay contact welding Zero cross signal is detected when the fusing relay is deactivated. This SC is detected when: • The main power is turned on. • The machine returns from the engine-off mode. • The interlock switch is deactivated.
• Causes: • Damaged fusing relay • Fusing relay drive circuit failure
• Remedy: 1. Make sure that the harness between the AC controller board and BiCU is firmly connected. 2. Replace the AC controller board. 3. Replace the BiCU.

• Code: 547-02
• Description: Zero cross error: fusing lamp relay contact defective Zero cross signal cannot be detected if the fusing relay is activated. This SC is detected when: • The main power is turned on. • The machine returns from the engine-off mode. • The interlock switch is turned off or on.
• Causes: • Broken fusing relay (open circuit) • Fusing relay circuit failure • PSU fuse (24VS) worn out
• Remedy: 1. Make sure that the harness between the AC controller board and BiCU is firmly connected. 2. Replace the AC controller board. 3. Replace the BiCU.

• Code: 547-03
• Description: Zero cross error: low frequencies error The frequency of the power source is lower than 44Hz. This SC is detected when the main power is ON.
• Causes: • Unstable frequency
• Remedy: 1. Check the frequency is 45Hz or more. If not, the power supply from the wall socket may be the cause. Ask for your supervisor or the electrician in charge at the site. 2. Replace the AC controller board.

• Code: 549-00
• Description: Fusing Center Low Temperature After passing 60 seconds when FGATE is On, thermopile 1 (thermistor 1) detects a temperature of -100 degrees C from the compensated target temperature for consecutive 60 seconds.
• Causes: • Fusing lamp disconnection during paper passing • Loose connector
• Remedy: • Check the input voltage and replace the power plug. • Replace the fusing thermostat • Replace the fusing lamp. • Replace the fusing thermopile • Replace the AC controller board or BiCU.

• Code: 554-00
• Description: Fusing thermistor (NC sensor) detects high temperature (Hard) Fusing thermistor (NC sensor) detects the prescribed temperature.
• Causes: • Shorted triac • IOB failure • BiCU failure • Fusing unit: out of control
• Remedy: Do the following steps: 1. Reconnect the connector between the fusing unit and the BiCU. 2. Replace the thermistor. 3. Replace the harness between the fusing unit and the BiCU. 4. Replace the BiCU. 5. Replace the AC controller board. • Replace the fusing unit if all the above steps cannot solve the issue.