• Code: L3-00
• Description: Scanner return trouble
  Scanner return is not completed within the specified time.
• Causes: Scanner unit trouble SCU PWB trouble Scanner control PWB trouble Harness and connector connection trouble Scanner home position sensor trouble Scanner motor trouble
• Remedy: Use SIM1-1 to check the scan operation. Replace the scanner unit. Replace the SCU PWB. Check connection of the connectors and the harness. Replace the scanner home position sensor. Replace the scanner motor.

• Code: L4-02
• Description: Paper feed motor trouble
  A lock signal is not detected within the specified time in ON operation of the paper feed motor after warming-up or canceling a jam.
• Causes: Paper feed motor trouble Paper feed motor harness and connector connection trouble PCU PWB trouble
• Remedy: Use SIM6-1 to check the operation of the paper feed motor. Replace the paper feed motor. Check connection of the paper feed motor harness and the connector. Replace the PCU PWB.

• Code: L4-03
• Description: Fusing motor trouble
  The motor lock signal is detected during rotation of the fusing motor.
• Causes: Fusing motor trouble Fusing motor harness and connector connection trouble PCU PWB trouble
• Remedy: Use SIM6-1 to check the operation of the fusing motor. Replace the Fusing motor. Check connection of the fusing motor harness and the connection. Replace the PCU PWB.

• Code: L4-04
• Description: Developing motor trouble (BLACK)
  The motor lock signal is detected during rotation of the developing motor.
• Causes: Developing motor trouble Developing motor harness and connector connection trouble PCU PWB trouble Developing unit trouble
• Remedy: Use SIM25-1 to check the operation of the developing motor. Replace the developing motor. Check connection of the developing motor harness and the connection. Replace the PCU PWB. Replace the developing motor. Replace the developing unit.

• Code: L4-05
• Description: Developing motor trouble (COLOR)
  The motor lock signal is detected during rotation of the developing motor.
• Causes: Developing motor trouble Developing motor harness and connector connection trouble PCU PWB trouble Developing unit trouble
• Remedy: Use SIM25-1 to check the operation of the developing motor. Replace the developing motor. Check connection of the developing motor harness and the connection. Replace the PCU PWB. Replace the developing motor. Replace the developing unit.

• Code: L4-06
• Description: Transfer unit lift trouble
  A change in the primary transfer position sensor cannot be detected within the specified time in lifting operation of the primary transfer unit.
• Causes: Transfer unit position sensor trouble Dirt on the transfer unit position sensor. PCU PWB trouble Connection trouble of the connector and the harness. Transfer unit lift mechanism trouble Primary transfer belt unit is not installed.
• Remedy: Use SIM6-3 to check the separating operation of the transfer unit. Install the primary transfer belt unit. Replace the transfer unit position sensor. Clean the transfer unit position sensor. Replace the PCU PWB. Check connection of the connector and the harness. Repair the transfer unit lift mechanism.

• Code: L4-07
• Description: Transfer belt motor trouble
• Causes: The motor lock signal is detected during rotation of the transfer belt motor. Transfer belt motor trouble Transfer belt motor harness and connector connection trouble PCU PWB trouble
• Remedy: Use SIM25-1 to check the operation of the transfer belt motor. Check the transfer belt motor, and replace if necessary. Check connection of the harness and connectors of the transfer belt motor, and replace if necessary. Check the PCU PWB, and replace if necessary.

• Code: L4-11
• Description: Shift motor trouble
  No change in the shifter home position sensor signal is detected in the operation of the shifter initializing.
• Causes: Shift motor trouble. PCU PWB trouble. Connection trouble of the connector and the harness. Shifter home position sensor trouble.
• Remedy: Use SIM6-1 to check the shift operation. Use SIM30-1 to check the operation of the shifter home position sensor. Replace the shift motor. Replace the PCU PWB. Check connection of the connector and the harness. Replace the shifter home position sensor.