• Code: 555
• Description: Fusing lamp overheat error (rear)
  After the fusing temperature reaches the target temperature, the fusing lamp does not turn off for 20 consecutive seconds.
• Causes: • Fusing thermistor defective or out of position • Power supply board defective

• Code: 556
• Description: Unstable fusing temperature (rear)
  The fusing temperature varies 50°C or more within 1 second, and this occurs 2 consecutive times.
• Causes: • Thermistor defective or out of position • Power supply unit defective

• Code: 590
• Description: Left exhaust fan motor error
  The CPU detects an exhaust fan lock signal for more than 5 seconds.
• Causes: • Loose connection of the exhaust fan motor • Too much load on the motor drive

• Code: 591
• Description: Rear exhaust fan motor error
  The CPU detects an exhaust fan lock signal for more than 5 seconds.
• Causes: • Loose connection of the exhaust fan motor • Too much load on the motor drive

• Code: 620
• Description: Communication error between BICU and ADF
  The BICU does not receive a response from the ADF main board for 4 seconds or more. The BICU receives a break signal from the ADF main board.
• Causes: • Poor connection between the BICU and ADF main board (DF connector) • ADF main board defective • BICU defective

• Code: 621
• Description: ADF connection error
  An incorrect ADF (an ADF for some other copier) is detected. (for Basic and MFP machines) An ADF (including the correct ADF) is installed while the copier is in the energy saver mode. (for MFP machine only)
• Causes: • ADF incorrect (The ADF for B039/B040/B043 is installed on a B121/B122/B123.) • The connector of the ADF is removed while the machine is in the energy saver mode.

• Code: 632
• Description: Accounting error 1
  An error is detected during the communication with the MF accounting device.
• Causes: • Accounting device defective • Loose connection

• Code: 633
• Description: Accounting error 2
  After communication is established with the MF accounting device, a brake signal is issued.
• Causes: • Accounting device defective • Loose connection