• Code: 391
• Description: Development bias leak
  A development bias leak signal is detected.
• Causes: • Poor connection of the PCU • High voltage supply board defective

• Code: 392
• Description: TD sensor initial setting error
  TD sensor output voltage falls out of the adjustment range (2.0 +- 0.2 V) after the TD sensor initial setting has been finished.
• Causes: • Someone forgot to remove the toner seal of the PCU • ID sensor defective • TD sensor abnormal • Drum does not turn • Development roller does not turn • Poor connection of the PCU

• Code: 401
• Description: Transfer roller leak error 1
  A transfer roller current leak signal is detected. The current feedback signal for the transfer roller is not detected.
• Causes: • High voltage supply board defective • Poor connection of the PCU • Transfer/separation unit set incorrectly • Transfer roller damaged

• Code: 402
• Description: Transfer roller leak error 2
  A transfer roller current leak signal is detected. The current feedback signal for the transfer roller is not detected.
• Causes: • High voltage supply board defective • Poor connection of the PCU • Transfer/separation unit set incorrectly • Transfer roller damaged

• Code: 411
• Description: Separation bias leak error
  A separation bias leak signal is detected.
• Causes: • High voltage supply board defective • Poor connection of the PCU • Discharge plate defective

• Code: 490
• Description: Toner supply motor leak error
  Over 1 A supplied to the toner supply motor for longer than 200 ms.
• Causes: Toner supply motor defective

• Code: 500
• Description: Main motor lock
  A main motor lock signal is not detected for more than 500 ms after the main motor starts to rotate, or the lock signal is not detected for more than 500 ms during rotation after the last signal.
• Causes: • Too much load on the drive mechanism • Main motor defective

• Code: 501
• Description: 1st paper tray lift motor malfunction
• Causes: • Paper lift sensor defective • Tray lift motor defective • Too much load on the drive mechanism • Poor tray lift motor connection