• Code: E304
• Description: Heating Roller warm-up failure
  - The Heating Roller Thermistor/1 (TH1) and the Heating Roller Thermistor/2 (TH3) fails to raise a given degree of temperature even after the lapse of a given period of time after the Heating Roller Heater lamp/1 (H1) is turned ON.
  - The detected temperature of the Heating Roller Thermistor/1 (TH1) is lower for a given level of degree than one of the Fusing Pressure Roller Thermistor/1 (TH2) after the Front Cover is opened or closed, the Main Power Switch is turned ON, or TROUBLE RESET is implemented.
  - The counter value of zero cross signal input is not updated for a given period of time.
• Causes: • Fusing Unit • DC Power Supply (PU1) • Mechanical Control Board (PWB-M)
• Remedy: 1 Check the Fusing Unit for correct installation (whether it is secured in position). - - 2 Check the Fusing Unit, PWB-M and PU1 for proper connection and correct or change as necessary. - - 3 Change Fusing Unit - - 4 Change PWB-M - - 5 Change PU1

• Code: E305
• Description: Fusing Pressure Roller warm-up failure
  - The Fusing Pressure Roller Thermistor/1 (TH2) fails to raise a given degree of temperature even after the lapse of a given period of time after the Fusing Pressure Heater Lamp (H3) is turned ON.
  - The detected temperature of the Fusing Pressure Roller Thermistor/1 (TH2) is lower for a given level of degree than one of the Heating Roller Thermistor/1 (TH1) after the Front Cover is opened or closed, the Main Power Switch is turned ON, or TROUBLE RESET is implemented.
• Causes: • Fusing Unit • DC Power Supply (PU1) • Mechanical Control Board (PWB-M)
• Remedy: 1 Check the Fusing Unit for correct installation (whether it is secured in position). - - 2 Check the Fusing Unit, PWB-M and PU1 for proper connection and correct or change as necessary. - - 3 Change Fusing Unit - - 4 Change PWB-M - - 5 Change PU1

• Code: E310
• Description: Fusing Unit New Article Release
  - A new installation is not detected when a new Fusing Unit is installed.
• Causes: • Fusing Unit • Mechanical Control Board (PWB-M)
• Remedy: 1 Check the Fusing Unit for correct installation (whether it is secured in position). - - 2 Check the Fusing Unit, PWB-M for proper connection and correct or change as necessary. - - 3 Reinstall Fusing Unit - - 4 Change Fusing Unit - - 5 Change PWB-M

• Code: E400
• Description: Abnormally low toner density detected Cyan TCR Sensor
  - Mixture ratio of the toner and carrier in the developing machine is lower than the specified value.
• Causes: • Photoconductor Unit/C • Photoconductor Unit/M • Photoconductor Unit/Y • Toner Supply Motor Y/M (M6) • Toner Supply Motor C/K (M7) • Mechanical Control Board (PWB-M) • Controller Board (PWB-P)
• Remedy: 1 Perform image troubleshooting procedure if image density is low. - - 2 Clean the TCR Sensor window on the underside of the Photoconductor Unit if dirty. - - 3 M6, M7 operation check PWB-M CNDM2-10 to 13(M6) PWB-M CNDM3-10 to 13(M7) C-22 C-23 4 Reinstall Photoconductor Unit. - - 5 Change Photoconductor Unit. - - 6 Change PWB-M - - 7 Change PWB-P

• Code: E401
• Description: Abnormally high toner density detected Cyan TCR Sensor
  - Mixture ratio of the toner and carrier in the developing machine is higher than the specified value.
• Causes: • Photoconductor Unit/C • Photoconductor Unit/M • Photoconductor Unit/Y • Mechanical Control Board (PWB-M) • Controller Board (PWB-P)
• Remedy: 1 Clean the TCR Sensor window on the underside of the Photoconductor Unit if dirty. - - 2 Reinstall Photoconductor Unit. - - 3 Change Photoconductor Unit. - - 4 Change PWB-M - - 5 Change PWB-P

• Code: E402
• Description: Abnormally low toner density detected Magenta TCR Sensor
  - Mixture ratio of the toner and carrier in the developing machine is lower than the specified value.
• Causes: • Photoconductor Unit/C • Photoconductor Unit/M • Photoconductor Unit/Y • Toner Supply Motor Y/M (M6) • Toner Supply Motor C/K (M7) • Mechanical Control Board (PWB-M) • Controller Board (PWB-P)
• Remedy: 1 Perform image troubleshooting procedure if image density is low. - - 2 Clean the TCR Sensor window on the underside of the Photoconductor Unit if dirty. - - 3 M6, M7 operation check PWB-M CNDM2-10 to 13(M6) PWB-M CNDM3-10 to 13(M7) C-22 C-23 4 Reinstall Photoconductor Unit. - - 5 Change Photoconductor Unit. - - 6 Change PWB-M - - 7 Change PWB-P

• Code: E403
• Description: Abnormally high toner density detected Magenta TCR Sensor
  - Mixture ratio of the toner and carrier in the developing machine is higher than the specified value.
• Causes: • Photoconductor Unit/C • Photoconductor Unit/M • Photoconductor Unit/Y • Mechanical Control Board (PWB-M) • Controller Board (PWB-P)
• Remedy: 1 Clean the TCR Sensor window on the underside of the Photoconductor Unit if dirty. - - 2 Reinstall Photoconductor Unit. - - 3 Change Photoconductor Unit. - - 4 Change PWB-M - - 5 Change PWB-P

• Code: E404
• Description: Abnormally low toner density detected Yellow TCR Sensor
  - Mixture ratio of the toner and carrier in the developing machine is lower than the specified value.
• Causes: • Photoconductor Unit/C • Photoconductor Unit/M • Photoconductor Unit/Y • Toner Supply Motor Y/M (M6) • Toner Supply Motor C/K (M7) • Mechanical Control Board (PWB-M) • Controller Board (PWB-P)
• Remedy: 1 Perform image troubleshooting procedure if image density is low. - - 2 Clean the TCR Sensor window on the underside of the Photoconductor Unit if dirty. - - 3 M6, M7 operation check PWB-M CNDM2-10 to 13(M6) PWB-M CNDM3-10 to 13(M7) C-22 C-23 4 Reinstall Photoconductor Unit. - - 5 Change Photoconductor Unit. - - 6 Change PWB-M - - 7 Change PWB-P