• Code: E020-0340
• Description: ATR Sensor (Bk) error or toner supply error
  Unable to adjust the control voltage at the time of ATR Sensor (Bk) initialization.
• Remedy: 1. Check if the Drum Unit (Bk) is installed. 2. Check the Drum Unit Relay PCB (Bk) (UN29) 3. Check the Drum Unit Memory PCB (Bk) (UN33) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (Bk) (UN29). 5. Replace the Drum Unit (Bk). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0341
• Description: ATR Sensor (Bk) error or toner supply error
  Unable to adjust the control voltage at the time of ATR Sensor (Bk) initialization.
• Remedy: 1. Check if the Drum Unit (Bk) is installed. 2. Check the Drum Unit Relay PCB (Bk) (UN29) 3. Check the Drum Unit Memory PCB (Bk) (UN33) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (Bk) (UN29). 5. Replace the Drum Unit (Bk). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0350
• Description: ATR patch failed to be created correctly or Patch Sensor error
  High density for the target at patch detection
• Remedy: 1. Clean the scanner’s window. 2. Use your hand to check if the shutter of the Registration Patch Sensor Unit can be open. 3. Check if the window of the Patch Sensor (UN43/ UN44) is soiled. 4. Check scar on the ITB. 5. Check movement of the Registration Shutter Solenoid (SL02). COPIER > FUNCTION > PART-CHK > SL to move SL02 6. Check the harness/connector between the DC Controller PCB (UN09/J12) and the Patch Sensors (UN43/J4007, UN44, J4006). 7.Replace the Drum Unit (Bk) 8.Replace the Registration Patch Sensor Unit 9 Replace the ITB Unit. 10. Check conduction of the fuses (FU5, FU8) in the DC Controller PCB (UN09). 11. Replace the Primary Transfer High Voltage PCB (UN04) 12. Replace the Developing High Voltage PCB (UN07) 13. Replace the Primary Charging High Voltage PCB (UN06) 14. Replace the Auxiliary High Voltage PCB (UN08) 15. Replace the Replace the DC Controller PCB (UN09)

• Code: E020-0360
• Description: ATR patch failed to be created correctly or Patch Sensor error
  High density for the target at patch detection
• Remedy: 1. Check the patch shape. 2. Clean the high voltage contact point with dry wiping or air blower. 3. Check the harness/connector between the DC Controller (UN09) and the High Voltage PCB. Between the DC Controller PCB (UN09/ J21) and the Primary Charging High Voltage PCB (UN06/ J441, J442) Between the DC Controller PCB (UN09/ J21, J22) and the Developing High Voltage PCB (UN07/ J451, J452) Between the DC Controller PCB (UN09/ J19) and the Auxiliary High Voltage PCB (UN08/J461, J462) Between the DC Controller PCB (J205) and the Primary Transfer High Voltage PCB (UN04/J1001) 4. Replace the Drum Unit (Bk) 5. Replace the Registration Patch Sensor Unit 6. Replace the ITB Unit. 7. Check conduction of the fuses (FU5, FU8) in the DC Controller PCB (UN09). 8. Replace the Primary Transfer High Voltage PCB (UN04) 9. Replace the Developing High Voltage PCB (UN07) 10. Replace the Primary Charging High Voltage PCB (UN06) 11. Replace the Auxiliary High Voltage PCB (UN08) 12. Replace the DC Controller PCB (UN09)

• Code: E020-0390
• Description: ATR Sensor (Bk) error or toner supply error
  The average of ATR Sensor (Bk) detection value is the specified value or lower.
• Remedy: 1. Check if the Drum Unit (Bk) is installed. 2. Check the Drum Unit Relay PCB (Bk) (UN29) 3. Check the Drum Unit Memory PCB (Bk) (UN33) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (Bk) (UN29). 5. Replace the Drum Unit (Bk). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0391
• Description: ATR Sensor (Bk) error or toner supply error
  The average of ATR Sensor (Bk) detection value is the specified value or higher.
• Remedy: 1. Check if the Drum Unit (Bk) is installed. 2. Check the Drum Unit Relay PCB (Bk) (UN29) 3. Check the Drum Unit Memory PCB (Bk) (UN33) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (Bk) (UN29). 5. Replace the Drum Unit (Bk). 6. Replace the DC Controller PCB (UN09)

• Code: E020-03B0
• Description: ATR Sensor (Bk) error or toner supply error
  The T/D ratio detected by the ATR Sensor (Bk) (UN42) is equal to or higher than the specified value (high density)
• Remedy: 1. Check if the Drum Unit (Bk) is installed. 2. Check the Drum Unit Relay PCB (Bk) (UN29) 3. Check the Drum Unit Memory PCB (Bk) (UN33) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (Bk) (UN29). 5. Replace the Drum Unit (Bk). 6. Replace the DC Controller PCB (UN09)

• Code: E020-03B1
• Description: ATR Sensor (Bk) error or toner supply error
  Error in detected delta T/D ratio The T/D ratio detected by the ATR Sensor (Bk) (UN42) is equal to or lower than the specified value (light density)
• Remedy: Overload of the motor or motor failure 1. Check conduction of FU9 on the DC Controller PCB (UN09). 2. Check the harness/connector between the DC Controller PCB (UN09/J26) and PS09 3. Replace the DC Controller PCB (UN09) 4. Check the Hopper Unit (Bk). 5. Replace the Hopper Unit (Bk).