• Code: U2-91
• Description: PCU PWB EEPROM check sum error
• Causes: PCU PWB EEPROM trouble PCU PWB trouble EEPROM socket contact trouble
• Remedy: Replace the PCU PWB EEPROM. Replace the PCU PWB. Check contact of the EEPROM socket. Use SIM16 to cancel the trouble. (The check sum error detection data are calculated again to reset the proper check sum data.)

• Code: U6-00
• Description: PCU PWB - Paper feed desk (paper feed tray 3, 4) communication trouble
• Causes: Connection trouble of the connector and the harness. Paper feed desk control PWB trouble PCU PWB trouble
• Remedy: Check connection of the connector and the harness. Replace the paper feed desk control PWB. Replace the PCU PWB.

• Code: U6-01
• Description: Desk paper feed tray 1 lift trouble
  D1ULD does not turn ON within the specified time when lift-up operation.
• Causes: D1ULD sensor trouble. Desk control PWB trouble. Lift unit trouble. Connection trouble of the connector and the harness. PCU PWB trouble.
• Remedy: Replace the D1ULD sensor. Replace the desk control PWB. Replace the lift unit. Check connection of the connector and the harness. Replace the PCU PWB.

• Code: U6-02
• Description: Desk paper feed tray 2 lift trouble
  D2ULD does not turn ON within the specified time when lift-up operation.
• Causes: D2ULD sensor trouble Desk control PWB trouble Lift unit trouble Connection trouble of the connector and the harness. PCU PWB trouble
• Remedy: Replace the D2ULD sensor. Replace the desk control PWB. Replace the lift unit. Check connection of the connector and the harness. Replace the PCU PWB.

• Code: U6-09
• Description: LCC lift motor trouble
  No variation in the motor rotation sensor signal (encoder sign) is detected within the specified time after booting or stopping the LCC lift motor.
• Causes: LCC lift motor rotation sensor trouble LCC control PWB trouble LCC lift mechanism trouble LCC lift motor trouble
• Remedy: Use SIM4-2 and 4-3 to check the operation of the LCC sensor and the lift motor. Check the LCC lift motor rotation sensor, and replace if necessary. Check the LCC control PWB, and replace if necessary. Check the LCC lift mechanism, and repair if necessary. Check the LCC lift motor, and replace if necessary. Use SIM15 to cancel the trouble.

• Code: U6-10
• Description: Desk paper feed unit paper transport motor trouble
• Causes: Desk paper feed motor trouble (motor lock, motor rpm abnormality, over-current to the motor). Desk control PWB trouble Connection trouble of the connector and the harness.
• Remedy: Use SIM4-3 to check the operation of the desk transport motor. Replace the desk control PWB. Replace the desk paper feed motor. Check connection of the connector and the harness.

• Code: U6-20
• Description: LCC control PWB - PCU PWB communication error
• Causes: Communication error between the LCC control PWB and the PCU PWB. Connection trouble of the harness and the connector between the machine and the LCC and those of the LCC control PWB. LCC control PWB trouble PCU PWB trouble Malfunction due to noises.
• Remedy: Check to confirm the LCC model. Check the connection of the harness and the connector between the machine and the LCC and those of the LCC control PWB, and replace if necessary. Check the LCC control PWB, and replace if necessary. Check the PCU PWB, and replace if necessary.

• Code: U6-21
• Description: LCC transport motor trouble
  No variation in the motor rotation sensor signal (encoder sign) is detected within the specified time after booting or stopping the LCC transport motor.
• Causes: LCC transport motor rotation sensor trouble LCC control PWB trouble LCC paper transport mechanism trouble LCC paper transport motor trouble
• Remedy: Use SIM4-3 to check the operation of the LCC transport motor. Check the LCC transport motor rotation sensor, and replace if necessary. Check the LCC control PWB, and replace if necessary. Check the LCC paper transport mechanism, and replace if necessary. Check the LCC transport motor, and replace if necessary.