• Code: F2-43
• Description: Toner density sensor trouble (Y)
• Causes: Toner density sensor output abnormality. Sensor connector and harness connection trouble. Developing unit trouble. PCU PWB trouble.
• Remedy: Replace the toner density sensor. Check connection of the sensor connector and the harness. Replace the developing unit. Replace the PCU PWB.

• Code: F2-45
• Description: Color image density sensor trouble
• Causes: Color image density sensor sensitivity adjustment trouble. Color image density sensor trouble. Sensor harness and connector connection trouble. Image density sensor dirt. Calibration plate dirt. Transfer unit lift operation trouble PCU PWB trouble.
• Remedy: Replace the color image density sensor. Check connection of the sensor harness and the connector. Clean the image density sensor. Replace the calibration plate. Repair the transfer unit lift mechanism. Replace the PCU PWB. Use SIM44-13 to perform the sensitivity adjustment of the process control sensor.

• Code: F2-49
• Description: LSU thermistor trouble
• Causes: The LSU temperature is outside of -28„aC - 78„aC. LSU thermistor trouble. LSU thermistor harness and connector connection trouble PCU PWB trouble. LSU control PWB trouble.
• Remedy: Replace the PCU PWB. Replace the LSU control PWB. Replace the LSU.

• Code: F2-50
• Description: K drum phase sensor trouble
• Causes: Drum phase sensor trouble. Drum phase sensor harness and connector
  connection trouble Drum drive section trouble. PCU PWB trouble.
• Remedy: Use SIM30-1 to check the operation of "DHPD_K". Replace the drum phase sensor. Check connection of the drum phase sensor harness and the connector. Repair the drum drive section. Replace the PCU PWB.

• Code: F2-51
• Description: CL drum phase sensor trouble
• Causes: Drum phase sensor trouble. Drum phase sensor harness and connector connection trouble Drum drive section trouble. PCU PWB trouble.
• Remedy: Use SIM30-1 to check the operation of "DHPD_CL". Replace the drum phase sensor. Check connection of the drum phase sensor harness and the connector. Repair the drum drive section. Replace the PCU PWB.

• Code: F2-58
• Description: Temperature/humidity sensor trouble (HUD_M/TH_M)
• Causes: Temperature/humidity sensor trouble. Process humidity sensor harness and connector connection trouble PCU PWB trouble.
• Remedy: Replace the temperature/humidity sensor. Check connection of the temperature/humidity sensor harness and the connector. Replace the PCU PWB.

• Code: F2-64
• Description: Toner supply operation trouble (K)
• Causes: Toner motor trouble. Toner density sensor trouble. Connector/harness trouble. PCU PWB trouble. Toner cartridge trouble. Developing unit trouble. Toner transport pipe section trouble
• Remedy: Replace the toner motor. Replace the toner density sensor. Connector and harness check. Replace the PCU PWB. Replace the toner cartridge. Replace the developing unit. Check the toner transport pipe section.

• Code: F2-65
• Description: Toner supply operation trouble (C)
• Causes: Toner motor trouble. Toner density sensor trouble. Connector/harness trouble. PCU PWB trouble. Toner cartridge trouble. Developing unit trouble. Toner transport pipe section trouble
• Remedy: Replace the toner motor. Replace the toner density sensor. Connector and harness check. Replace the PCU PWB. Replace the toner cartridge. Replace the developing unit. Check the toner transport pipe section.