• Code: E020-0190
• Description: ATR Sensor (M) error or toner supply error
  The average of ATR Sensor (M) detection value is the specified value or lower.
• Remedy: 1. Check if the Drum Unit (M) is installed. 2. Check the Drum Unit Relay PCB (M) (UN27). 3. Check the Drum Unit Memory PCB (M) (UN31). 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (M) (UN27). 5. Replace the Drum Unit (M). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0191
• Description: ATR Sensor (M) error or toner supply error
  The average of ATR Sensor (M) detection value is the specified value or higher.
• Remedy: 1. Check if the Drum Unit (M) is installed. 2. Check the Drum Unit Relay PCB (M) (UN27). 3. Check the Drum Unit Memory PCB (M) (UN31). 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (M) (UN27). 5. Replace the Drum Unit (M). 6. Replace the DC Controller PCB (UN09)

• Code: E020-01B0
• Description: ATR Sensor (M) error or toner supply error
  The T/D ratio detected by the ATR Sensor (M) (UN40) is equal to or higher than the specified value (high density)
• Remedy: 1. Check if the Drum Unit (M) is installed. 2. Check the Drum Unit Relay PCB (M) (UN27). 3. Check the Drum Unit Memory PCB (M) (UN31). 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (M) (UN27). 5. Replace the Drum Unit (M). 6. Replace the DC Controller PCB (UN09)

• Code: E020-01B1
• Description: ATR Sensor (M) error or toner supply error
  Error in detected delta T/D ratio The T/D ratio detected by the ATR Sensor (M) (UN40) is equal to or lower than the specified value (light density)
• Remedy: Overload of the motor or motor failure 1. Check conduction with FU2 on the DC Controller PCB (UN09) 2. Check the harness/connector between the DC Controller PCB (UN09/J24) and PS07. 3. Replace the DC Controller PCB (UN09) 4. Check the Hopper Unit (M) 5. Replace the Hopper Unit (M).

• Code: E020-0220
• Description: ATR Sensor (C) error or toner supply error
  Error in detected TD ratio. The average of ATR reference value is the specified value or lower at the time of ATR Sensor (C) initialization.
• Remedy: 1. Check if the Drum Unit (C) is installed. 2. Check the Drum Unit Relay PCB (C) (UN28) 3. Check the Drum Unit Memory PCB (C) (UN32) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (C) (UN28). 5. Replace the Drum Unit (C). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0230
• Description: ATR Sensor (C) error or toner supply error
  Error in detected TD ratio. The average of ATR reference value is the specified value or higher at the time of ATR Sensor (C) initialization.
• Remedy: 1. Check if the Drum Unit (C) is installed. 2. Check the Drum Unit Relay PCB (C) (UN28) 3. Check the Drum Unit Memory PCB (C) (UN32) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (C) (UN28). 5. Replace the Drum Unit (C). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0240
• Description: ATR Sensor (C) error or toner supply error
  Unable to adjust the control voltage at the time of ATR Sensor (C) initialization.
• Remedy: 1. Check if the Drum Unit (C) is installed. 2. Check the Drum Unit Relay PCB (C) (UN28) 3. Check the Drum Unit Memory PCB (C) (UN32) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (C) (UN28). 5. Replace the Drum Unit (C). 6. Replace the DC Controller PCB (UN09)

• Code: E020-0241
• Description: ATR Sensor (C) error or toner supply error
  Unable to adjust the control voltage at the time of ATR Sensor (C) initialization.
• Remedy: 1. Check if the Drum Unit (C) is installed. 2. Check the Drum Unit Relay PCB (C) (UN28) 3. Check the Drum Unit Memory PCB (C) (UN32) 4. Check the harness/connector between the DC Controller PCB (UN09/ J25) and the Drum Unit Relay PCB (C) (UN28). 5. Replace the Drum Unit (C). 6. Replace the DC Controller PCB (UN09)