• Code: U2-04
• Description: EEPROM read/write error (Serial communication error)
  EEPROM access process error
• Causes: EEPROM abnormality
• Remedy: Check that the EEPROM is properly set. Use SIM 16 to cancel the trouble. Replace the MCU PWB.

• Code: U2-11
• Description: Counter check sum error (EEPROM)
  Check sum error of the counter area in the EEPROM
• Causes: EEPROM abnormality
• Remedy: Check that the EEPROM is properly set. Use SIM 16 to cancel the trouble. Replace the MCU PWB.

• Code: U9-00
• Description: Panel board communication trouble.
  Communication trouble with the panel board.
• Causes: No command can be sent from the MCU to the panel.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).

• Code: U9-80
• Description: Panel board communication trouble (Protocol).
  An error occurs in communication between MCU -Panel PWB.
• Causes: MCU PWB - Panel PWB harness trouble/ Garbled data.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).

• Code: U9-81
• Description: Panel board communication trouble (Parity).
  A parity error occurs in communication between the MCU and the Panel PWB.
• Causes: MCU PWB - Panel PWB harness trouble/ Garbled data.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).

• Code: U9-82
• Description: Panel board communication trouble (Overrun).
  An overrun error occurs in communication between the MCU and the panel board.
• Causes: MCU PWB - Panel PWB harness trouble/ Garbled data.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).

• Code: U9-84
• Description: Panel board communication trouble (Framing).
  A framing error occurs in communication between the MCU and the Panel PWB.
• Causes: MCU PWB - Panel PWB harness trouble/ Garbled data.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).

• Code: U9-88
• Description: Panel board communication trouble (Time out).
  A time-out error occurs in communication between the MCU and the Panel PWB.
• Causes: A command is completely sent from the MCU to the panel.
• Remedy: MCU PWB - Panel PWB harness trouble. Replace the panel or the MCU PWB. Machine reset (Power OFF/ON).