• Code: 0121
• Description: EEPROM read error (drum PWB K)
  • When data is transmitted to the EEPROM on drum PWB K, the ACK signal is not returned within 1 s.
• Causes: Poor contact in the connector terminals.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC9 on the engine controller PWB and the continuity across the connector terminals. Repair or replace if necessary.
  Defective drum PWB K. Replace the black process unit.

• Code: 0122
• Description: EEPROM read error (drum PWB C)
  • When data is transmitted to the EEPROM on drum PWB C, the ACK signal is not returned within 1 s.
• Causes: Poor contact in the connector terminals.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC10 on the engine controller PWB and the continuity across the connector terminals. Repair or replace if necessary.
  Defective drum PWB C. Replace the cyan process unit.

• Code: 0123
• Description: EEPROM read error (drum PWB M)
  • When data is transmitted to the EEPROM on drum PWB M, the ACK signal is not returned within 1 s.
• Causes: Poor contact in the connector terminals. Defective drum PWB M.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC11 on the engine controller PWB and the continuity across the connector terminals. Repair or replace if necessary.
  Defective drum PWB M. Replace the magenta process unit.

• Code: 0124
• Description: EEPROM read error (drum PWB Y)
  • When data is transmitted to the EEPROM on drum PWB Y, the ACK signal is not returned within 1 s.
• Causes: Poor contact in the connector terminals.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC12 on the engine controller PWB and the continuity across the connector terminals. Repair or replace if necessary.
  Defective drum PWB Y. Replace the black process unit.

• Code: 0150
• Description: Backup memory device problem (Engine controller PWB)
  • An error occurs in backup data read or write for the engine controller PWB. • An error occurs in control area deletion.
• Causes: Defective engine controller PWB.
• Remedy: Defective engine controller PWB. Replace the engine controller PWB.

• Code: 0160
• Description: Backup memory data problem (Engine controller PWB)
  • Data for backup data check is changed at the check after startup.
• Causes: Defective engine controller PWB.
• Remedy: Defective engine controller PWB. Replace the engine controller PWB.

• Code: 0170
• Description: Total counts problem
  • A checksum error is detected in the main and sub backup memories for the total counters.
• Causes: Data damage of EEPROM.
• Remedy: Data damage of EEPROM. Contact the Service Administrative Division.

• Code: 0240
• Description: Main controller PWB communication problem
  • The main controller PWB does not respond 120 seconds after the power is turned on.
• Causes: Poor contact in the connector terminals. DIMM installed incorrectly. Defective engine interface PWB or main controller PWB.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC6 on the engine interface PWB and the connector on the main controller PWB. Repair or replace if necessary.
  DIMM installed incorrectly. Check the connection. Repair or replace if necessary.
  Defective engine interface PWB or main controller PWB. Replace the engine interface PWB or main controller and check for correct operation.