• Code: 7411
• Description: Drum unit type Mismatch error (K) Improper adaptation of the main unit and drum unit is detected.
• Remedy: Drum unit 1. Check if the drum unit of different models is attached, and replace it to the correct one. 2. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. Drum unit - Unit relay PWB Unit relay PWB - Main/Engine PWB(YC7) 3. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire.
  Unit relay PWB Replace the unit relay PWB.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7412
• Description: Drum unit type Mismatch error (C) Improper adaptation of the main unit and drum unit is detected.
• Remedy: Drum unit 1. Check if the drum unit of different models is attached, and replace it to the correct one. 2. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. Drum unit - Unit relay PWB Unit relay PWB - Main/Engine PWB(YC7) 3. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire.
  Unit relay PWB Replace the unit relay PWB.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7413
• Description: Drum unit type Mismatch error (M) Improper adaptation of the main unit and drum unit is detected.
• Remedy: Drum unit 1. Check if the drum unit of different models is attached, and replace it to the correct one. 2. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. Drum unit - Unit relay PWB Unit relay PWB - Main/Engine PWB(YC7) 3. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire.
  Unit relay PWB Replace the unit relay PWB.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7414
• Description: Drum unit type Mismatch error (Y) Improper adaptation of the main unit and drum unit is detected.
• Remedy: Drum unit 1. Check if the drum unit of different models is attached, and replace it to the correct one. 2. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. Drum unit - Unit relay PWB Unit relay PWB - Main/Engine PWB(YC7) 3. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire.
  Unit relay PWB Replace the unit relay PWB.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7601
• Description: ID sensor error (front) When the measured value of the ID sensor matches any of the following. The dark potential P/Swave is greater than 0.8V. If the light potential S-wave is lower than the dark potential S-wave. If the light potential P-wave is lower than the dark potential P-wave (+0.5V).
• Remedy: ID sensor 1. Clean the ID sensor surface. 2. Check how the ID sensor is attached. 3. Check if the error is detected after performing the calibration. 4. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. ID sensor - Main/Engine PWB (YC24) 5. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire. 6. Replace the ID sensor.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7602
• Description: ID sensor error (rear) When the measured value of the ID sensor matches any of the following. The dark potential P/Swave is greater than 0.8V. If the light potential S-wave is lower than the dark potential S-wave. If the light potential P-wave is lower than the dark potential P-wave (+0.5V).
• Remedy: ID sensor 1. Clean the ID sensor surface. 2. Check how the ID sensor is attached. 3. Check if the error is detected after performing the calibration. 4. Confirm that the wiring connector is firmly connected, and if necessary, connect the connector all the way in. ID sensor - Main/Engine PWB (YC24) 5. If the wiring is disconnected, short-circuited or has a ground fault, replace the wire. 6. Replace the ID sensor.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7611
• Description: Bias calibration reading value error (Black) During the calibration, the ID sensor cannot read a patch density on the primary transfer belt normally.
• Remedy: Primary transfer belt ID sensor 1. Unplug the power cord from the wall outlet, and wait five seconds. Then plug in the power cord and then turn on the power switch. 2. Execute [Calibration] using [Adjustment/Maintenance] of the system menu. 3. Check the occurrence of this service call error in the Event Log. 4. When the same service call error is detected again, clean if there is any dirt or stains on the primary transfer belt or the ID sensor surface. 5. Check whether or not the ID sensor shutter is open, by opening and closing the paper tray. 6. If not corrected, replace the primary transfer unit. 7. After performing the test print, if the poor density occurs, check whether there is any failure in the drum unit, developer unit, LSU.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.

• Code: 7612
• Description: Bias calibration reading value error (Cyan) During the calibration, the ID sensor cannot read a patch density on the primary transfer belt normally.
• Remedy: Primary transfer belt ID sensor 1. Unplug the power cord from the wall outlet, and wait five seconds. Then plug in the power cord and then turn on the power switch. 2. Execute [Calibration] using [Adjustment/Maintenance] of the system menu. 3. Check the occurrence of this service call error in the Event Log. 4. When the same service call error is detected again, clean if there is any dirt or stains on the primary transfer belt or the ID sensor surface. 5. Check whether or not the ID sensor shutter is open, by opening and closing the paper tray. 6. If not corrected, replace the primary transfer unit. 7. After performing the test print, if the poor density occurs, check whether there is any failure in the drum unit, developer unit, LSU.
  Main/Engine PWB 1. Check the engine firmware and upgrade to the latest version if necessary. 2. Replace the main/engine PWB.