• Code: E012-0403
• Description: Faulty signal with Bk drum encoder sensor 2
  The signal was not detected for 100 msec or more.
• Remedy: 1. Check connection of drum encoder sensor 2 (UN38). 2. Take out drum encoder sensor 2 to clean the Sensor. 3. Replace drum encoder sensor 2. 4. Check if the harness of the drum encoder sensor is faulty (replace the harness if it’s disconnected). 5. Replace the Drum Driver PCB (UN4).

• Code: E012-0404
• Description: Failure in Bk drum encoder sensor Wheel
  Failure is detected with the Bk drum encoder sensor Wheel
• Remedy: 1. Take out the drum encoder sensor to clean the Sensor (UN37, UN38) and the Wheel. 2. Replace the drum encoder sensor Wheel. 3. Replace the drum encoder sensor. 4. Replace the Drum Driver PCB (UN4).

• Code: E012-0405
• Description: Failure in Bk Drum Motor Control
  Unstable rotation of the Bk Drum Motor
• Remedy: 1. Check if the Drum is installed. 2. Take out the drum encoder sensor (UN37, UN38) to clean the Sensor and the Wheel. 3. Remove the Process Unit and then install (reinstall) the Process Unit. 4. Replace the Drum Unit. 5. Replace the Drum Driver PCB (UN4).

• Code: E012-0406
• Description: Failure in rotation of Bk Drum Motor
  The Bk Drum Motor is not rotating at the specified speed/ is stopped.
• Remedy: 1. Check connection of the connector with the Drum Motor (M4). 2. Check connection of the connector with Drum Driver PCB (UN4). 3. Check the ITB (to see if the ITB is displaced/damaged. Refer to E075 if the ITB is displaced). 4. Replace the ITB Cleaning Blade. 5. Replace the Drum Driver PCB (UN4).

• Code: E012-1000
• Description: Failure in rotation when ITB Motor is driven.
  The ITB Motor is not rotating at the specified speed/is stopped.
• Remedy: 1. Check connection of the connector with the ITB Motor (M13). 2. Check connection of the connector with the ITB Unit. 3. Check connection of the connector with the Drum Driver PCB (UN4). 4. Check the ITB (to see if the ITB is displaced or damaged. Refer to E075 if the ITB is displaced). 5. Replace the ITB Cleaning Blade. 6. Replace the Drum Driver PCB (UN4).

• Code: E012-1001
• Description: Failure is detected before ITB motor is driven.
  LOCK signal is detected Low before the ITB Motor is driven.
• Remedy: 1. Check the cable connected to the ITB Motor. 2. Check the cable connected to the Drum Driver PCB (UN4).

• Code: E012-2000
• Description: Failure in rotation of Drum Motors (in all colors) and ITB Motor
  Faulty rotation with all of the Motors at the same time (based on the assumption that all of the motors fail to rotate)
• Remedy: 1. Check the connector on the Drum Driver PCB (UN4). 2. Check the connector on the Relay Board (UN5). 3. Check the Interlock Switch. 4. Check the Drum Driver Harness.

• Code: E012-3000
• Description: Failure in drum encoder sensors (in all colors)
  The drum encoder sensors are faulty (in all colors) at the same time.
• Remedy: 1. Check the connector on the Drum Driver PCB (UN4). 2. FU3 is disconnected on the Drum Driver PCB (UN4) -> Check the harness & replace the Drum Driver PCB (UN4).