• Code: F2-42
• Description: Toner density sensor trouble (MAGENTA)
• Causes: Toner density sensor output abnormality (Sample level 25 or less, or 231 or above) Connection trouble of the connector and the harness. Developing unit trouble. MFPC PWB trouble
• Remedy: Replace the toner density sensor. Harness and connector connection trouble. Replace the developing unit. Replace the MFPC PWB.

• Code: F2-43
• Description: Toner density sensor trouble (YELLOW)
• Causes: Toner density sensor output abnormality (Sample level 25 or less, or 231 or above). Connection trouble of the connector and the harness. Developing unit trouble. MFPC PWB trouble.
• Remedy: Replace the toner density sensor. Harness and connector connection trouble. Replace the developing unit. Replace the MFPC PWB.

• Code: F2-45
• Description: K image density sensor trouble
• Causes: K image density sensor sensitivity adjustment trouble. K image density sensor trouble. Harness and connector connection trouble. K image density sensor dirt. Calibration plate dirt. Calibration plate solenoid trouble. MFPC PWB trouble.
• Remedy: Replace the K image density sensor. Check connection of the connectors and the harness. Clean the K image density sensor. Replace the calibration plate. Replace the calibration plate solenoid. Replace the PCU PWB. Use SIM44-2 to adjust the process control sensor sensitivity.

• Code: F2-47
• Description: Ozon duct thermister trouble
• Causes: The ozone duct thermister trouble. Harness and connector connection trouble between the ozone duct thermistor and the MFPC PWB. MFPC PWB trouble.
• Remedy: Check connection of the connectors and the harness between the ozone duct thermistor and the MFPC PWB. Replace the MFPC PWB.

• Code: F2-49
• Description: LSU thermister trouble
• Causes: The LSU detection temperature is outside of -28C - 78C. LSU thermister trouble. Harness and connector connection trouble. MFP PWB trouble LSU control PWB trouble.
• Remedy: Check connection of the connectors and the harness. Replace the MFPC PWB. Replace the LSU.

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

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

• Code: F2-58
• Description: Process humidity sensor trouble
• Causes: Process humidity sensor trouble. Harness and connector connection trouble. PMFPC PWB trouble.
• Remedy: Replace the process humidity sensor. Check connection of the connectors and the harness. Replace the MFPC PWB.