• Code: C0180
• Description: Machine number mismatch error
  Machine number of main PWB and engine PWB does not match.
• Causes: Data damage of EEPROM.
• Remedy: Data damage of EEPROM. Contact the Service Administrative Division.
  

• Code: C0620
• Description: FAX image DIMM problem
  DIMM is not installed correctly. DIMM cannot be accessed.
• Causes: DIMM installed incorrectly.
  Defective main PWB.
• Remedy: DIMM installed incorrectly. Check if the DIMM is inserted into the socket on the main PWB correctly.
  Defective main PWB. Replace the main PWB and check for correct operation.

• Code: C0630
• Description: DMA problem
  DMA transmission of image data does not complete within the specified period of time.
• Causes: Poor contact in the connector terminals.
  Defective main PWB.
• Remedy: Poor contact in the connector terminals. Check the connection the signal cable for CIS and the main PWB, and the continuity across the connector terminals. Repair or replace if necessary.
  Defective main PWB. Replace the main PWB and check for correct operation.

• Code: C0640
• Description: Hard disk drive problem
  The hard disk cannot be accessed.
• Causes: Poor contact in the connector terminals.
  Defective hard disk.
  Defective main PWB.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC49 on the main PWB and the connector on the hard disk. Repair or replace if necessary.
  Defective hard disk. Run U024 (HDD formatting) without turning the power off to initialize the hard disk. Replace the hard disk drive and check for correct operation if the problem is still detected after initialization.
  Defective main PWB. Replace the main PWB and check for correct operation.

• Code: C0650
• Description: FAX image DIMM check problem
  Improper DIMM is installed.
• Causes: DIMM installed incorrectly.
  DIMM of another machine is installed.
  Defective main PWB.
• Remedy: DIMM installed incorrectly. Check if the DIMM is inserted into the socket on the main PWB correctly.
  DIMM of another machine is installed. Perform maintenance mode U671 (RECOVERY FAX DIMM).
  Defective main PWB. Replace the main PWB and check for correct operation.

• Code: C0800
• Description: Image processing problem
  JAM05 is detected twice.
• Causes: Defective main PWB.
• Remedy: Defective main PWB. Replace the main PWB and check for correct operation.

• Code: C0830
• Description: Fax control PWB flash program area checksum error
  A checksum error occurred with the program of the fax control PWB.
• Causes: Defective fax software.
  Defective fax control PWB.
• Remedy: Defective fax software. Install the fax software.
  Defective fax control PWB. Replace the fax control PWB and verify the operation.

• Code: C0840
• Description: Faults of RTC
  The time is judged to go back based on the comparison of the RTC time and the current time or five years or more have passed.
• Causes: Defective main PWB.
  The battery is disconnected from the main PWB.
• Remedy: Defective main PWB. Replace the main PWB and check for correct operation.
  The battery is disconnected from the main PWB. Check visually and remedy if necessary.