• Code: 123
• Display: Inspection is required.
  123 : Error
• Description: Ambient humidity error or non connection of humidity sensor
• Remedy: Is the cable from the CU/PU board to the toner sensor board connected properly?
  Re-connect it properly. Replace the toner sensor board.

• Code: 124
• Display: Inspection is required.
  124 : Error
• Description: Ambient temperature error
• Remedy: Is the cable from the CU/PU board to the toner sensor board connected properly?
  Re-connect it properly. Replace the toner sensor board.

• Code: 127
• Display: Inspection is required.
  127 : Error
• Description: An error of exhaust fan of the Fuser
• Remedy: Is the fan's connector properly connected? Does the error occur again?
  Connect properly. Replace the fan's motor. Replace the PU board.

• Code: 128
• Display: Inspection is required. 128 : Error 05
• Description: Image drum fan error
• Remedy: Is the connector of the fan connected properly? Does the error occur again?
  Re-connect it properly. Replace the fan motor. Replace the CU/PU board.

• Code: 134
• Display: Inspection is required.
  134 : Error
• Description: LED head detection error (134=K)
• Remedy: Is the LED head installed properly? Is the LED head fuse broken? Does the error occur again?
  Install the LED head unit. Check the LED head fuse. Check the fuse. Turn off and on the MFP. Replace the LED head unit.

• Code: 153
• Display: Inspection is required.
  153 : Error
• Description: Image drum unit fuse-cut error
• Remedy: Is the image drum unit installed properly? Does the error occur again? Is the MFP recovered by replacing the toner sensor board.
  Re-install it. Turn off and on the MFP. Be sure of the cable connection from the CU/PU board to the toner sensor board, and then replace the toner sensor board. Replace the CU/PU board.

• Code: 163
• Display: Inspection is required.
  163 : Error
• Description: Toner sensor detection error (163=K). This error does not occur with the MFP in the factory shipped configuration.
• Remedy: Is the toner cartridge installed? Is the toner slide shutter set?
  Install the toner cartridge. Turn it to the fixed position. Turn off and on the MFP. Replace the toner sensor assembly.

• Code: 167
• Display: Inspection is required.
  167 : Error
• Description: Thermistor slope error
• Remedy: Does an error message appear? Does the error occur again? Yes Turn off and on the MFP. Turn off and on the MFP after leaving it for 30 minutes.