• Code: C0320
• Description: Power CPU communication problem
  A communication error is detected 10 times in succession.
• Causes: Defective engine PWB.
• Remedy: Replace the engine PWB and check for correct operation.

• 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 the main PWB and the the hard disk, and the continuity across the connector terminals. 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
  Incorrect DIMM is installed. If DIMM from another Fax System is installed.
• Causes: DIMM installed incorrectly. Original DIMM not installed.
  Defective main PWB.
• Remedy: DIMM installed incorrectly. Original DIMM not installed. Check if the DIMM is inserted into the socket on the main PWB correctly. Run U671, RECOVER FAX DIMM to clear back-up data.
  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: Replace the main PWB and check for correct operation.

• Code: C0820
• Description: Fax control PWB CG ROM checksum error (optional fax)
  A checksum error occurred with the CG ROM data 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: C0830
• Description: Fax control PWB flash program area checksum error (optional fax)
  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.