• Code: L4-12
• Description: Secondary transfer separation trouble
  A change in the separation sensor status cannot be detected within the specified time in separation operation of the secondary transfer.
• Causes: Secondary transfer separation mechanism trouble. Secondary transfer separation clutch trouble. Secondary transfer separation sensor trouble. Connection trouble of the connector and the harness. PCU PWB trouble.
• Remedy: Check or repair the secondary transfer separation mechanism. Replace the secondary transfer separation clutch. Replace the secondary transfer separation sensor. Replace the PCU PWB. Check connection of the connector and the harness.

• Code: L4-16
• Description: Fusing pressure release trouble
  A change in the fusing pressure release sensor signal cannot be detected within the specified time after outputting the fusing pressure release motor.
• Causes: Fusing pressure release sensor trouble. Fusing pressure release motor trouble. Pressure release drive gear and pressure release idle gear trouble. PCU PWB trouble. Connection trouble of the connector and the harness.
• Remedy: Replace the fusing pressure release sensor. Replace the fusing pressure release motor. Replace the pressure release drive gear and the pressure release idle gear. Replace the PCU PWB. Check connection of the connector and the harness.

• Code: L4-31
• Description: Paper exit cooling fan trouble
  The fan operation signal is not detected.
• Causes: Paper exit cooling fan trouble. PCU PWB trouble Connection trouble of the connector and the harness.
• Remedy: Check connection of the connectors and the harness. Use SIM6-2 to check the rotating operation of the fan. Replace the paper exit cooling fan. Replace the PCU PWB.

• Code: L4-32
• Description: Power source cooling fan trouble
  The fan operation signal is not detected.
• Causes: Power cooling fan trouble. PCU PWB trouble. Connection trouble of the connector and the harness.
• Remedy: Use SIM6-2 to check that the fan is actually rotating. Replace the power cooling fan. Replace the PCU PWB. Check connection of the connectors and the harness.

• Code: L4-34
• Description: LSU cooling fan trouble
• Causes: When the LSU cooling fan is operated, the fan operation signal is not detected within the specified time. LSU fan trouble. Harness, connector trouble. LSU mother PWB trouble.
• Remedy: Use SIM6-2 to check the fan operation. Check the LSU fan, and replace if necessary. Check the harness/connector, and replace if necessary. Check the LSU mother PWB, and replace if necessary.

• Code: L4-35
• Description: Fusing cooling fan trouble
  The fan operation signal is not detected.
• Causes: Fusing cooling fan trouble. PCU PWB trouble. Connection trouble of the connector and the harness.
• Remedy: Use SIM6-2 to check that the fan is actually rotating. Replace the fusing cooling fan. Replace the PCU PWB. Check connection of the connector and the harness.

• Code: L4-43
• Description: Paper exit cooling fan 2 trouble
  The fan operation signal is not detected.
• Causes: Paper exit cooling fan trouble. (Machine R side) PCU PWB trouble. Connection trouble of the connector and the harness.
• Remedy: Replace the fan. Replace the PCU PWB. Check the connector and the harness. Use SIM6-2 to check that the fan is actually rotating.

• Code: L4-50
• Description: Process fan trouble
  The fan operation signal is not detected.
• Causes: Process fan trouble. PCU PWB trouble. Connection trouble of the connector and the harness.
• Remedy: Check that the fan is rotating after turning ON the power. Replace the process fan. Replace the PCU PWB. Check connection of the connector and the harness.