Code :

Code: 623
Description: 3rd Paper Bank (option) communication error This SC is not issued for this machine. When a communication error signal between the 2nd paper bank and 3rd paper bank is received.
Causes: • Loose or disconnected connector
Remedy: Check the connection between the main machine and paper feed unit.

Code: 624
Description: 4th Paper Bank (option) communication error This SC is not issued for this machine. When a communication error signal between the 3rd paper bank and 4th paper bank is received.
Causes: • Loose or disconnected connector
Remedy: Check the connection between the main machine and paper feed unit.

Code: 669
Description: NVRAM error Retry of NVRAM communication fails three times after the machine has detected the NVRAM error.
Causes: Caused by noise
Remedy: Turn the main power switch off and on.

Code: 681
Description: RFID: Communication error • Communication error occurs at communication with the RFID receptor. • Retry of RFID communication failed
Causes: • Defective RFID reader and writer • Disconnected ASAP I/F • No memory chip on the toner cartridge • Noise
Remedy: 1. Remove and then re-insert each toner bottle. 2. Replace the toner bottle. 3. Confirm that RFID connectors and harnesses are connected correctly. 4. If the connectors and harnesses are damaged, replace the RFID_CPU board and Harness: ANTENNA: Toner Supply. 5. Replace the affected RFID_AFE board (KMCY). (See table below.) 6. Replace the BCU.

Code: 682
Description: Memory chip at TD sensor: Communication error Retry of memory chip communication fails three times after the machine has detected the memory chip communication error.
Causes: • Damaged memory chip data • Disconnected inter face • No memory chip on the development unit • Noise
Remedy: Replace the PCDU.

Code: 683
Description: RFID: Unit check error The machine gets RFID communication error even the toner cartridges have not been installed in the machine.
Causes: • Caused by noise
Remedy: Turn the main power switch off and on.

Code: 687
Description: Memory address command error The BCU does not receive a memory address command from the controller for the prescribed time after the paper has reached the registration sensor.
Causes: • Harness disconnection at BCU • Controller board loose or broken • Defective HDD • Defective BCU • Defective controller
Remedy: 1. Check if the controller is firmly connected to the BCU. 2. Update the firmware of the controller. 3. Replace the HDD. 4. Update the firmware of the BCU. 5. Replace the BCU. 6. Replace the controller.

Code: 690
Description: GAVD communication error • The I2C bus device ID is not identified during initialization. • A device-status error occurs during I2C bus communication. • The I2C bus communication is not established due to an error other than a buffer shortage.
Causes: • Loose connection • Defective BCU • Defective LD controller board
Remedy: 1. Turn the main switch off and on. 2. Check the cable connection. 3. Replace the laser unit. 4. Replace the BCU.