• Code: SC370
• Description: TD sensor detection abnormal (K) - Timing - When communicating with TD sensors, during printing process, or process control self-check - Condition - TD sensor output exceeds 4.5V or becomes lower than 0.5V.
• Causes: • Poor connection of TD sensor harness • Dirty sensor surface • Defective TD sensor • Toner density is out of range
• Remedy: 1. Check if the TD sensor connector is properly connected. 2. Clean the surface of the TD sensor. 3. Replace the TD sensor. If it becomes OK after the sensor is replaced, replace the developer of color related to the problem. If the problem is related to the toner density (too low or high), find a cause and fix it.

• Code: SC371
• Description: TD sensor detection abnormal (Y) - Timing - When communicating with TD sensors, during printing process, or process control self-check - Condition - TD sensor output exceeds 4.5V or becomes lower than 0.5V.
• Causes: • Poor connection of TD sensor harness • Dirty sensor surface • Defective TD sensor • Toner density is out of range
• Remedy: 1. Check if the TD sensor connector is properly connected. 2. Clean the surface of the TD sensor. 3. Replace the TD sensor. If it becomes OK after the sensor is replaced, replace the developer of color related to the problem. If the problem is related to the toner density (too low or high), find a cause and fix it.

• Code: SC372
• Description: TD sensor detection abnormal (C) - Timing - When communicating with TD sensors, during printing process, or process control self-check - Condition - TD sensor output exceeds 4.5V or becomes lower than 0.5V.
• Causes: • Poor connection of TD sensor harness • Dirty sensor surface • Defective TD sensor • Toner density is out of range
• Remedy: 1. Check if the TD sensor connector is properly connected. 2. Clean the surface of the TD sensor. 3. Replace the TD sensor. If it becomes OK after the sensor is replaced, replace the developer of color related to the problem. If the problem is related to the toner density (too low or high), find a cause and fix it.

• Code: SC373
• Description: TD sensor detection abnormal (M) - Timing - When communicating with TD sensors, during printing process, or process control self-check - Condition - TD sensor output exceeds 4.5V or becomes lower than 0.5V.
• Causes: • Poor connection of TD sensor harness • Dirty sensor surface • Defective TD sensor • Toner density is out of range
• Remedy: 1. Check if the TD sensor connector is properly connected. 2. Clean the surface of the TD sensor. 3. Replace the TD sensor. If it becomes OK after the sensor is replaced, replace the developer of color related to the problem. If the problem is related to the toner density (too low or high), find a cause and fix it.

• Code: SC385
• Description: ID sensor VSG adjustment error - Timing - During process control self check, the main control board detects that the signal of Vsg fed-back from the ID sensor is out of range.
• Causes: • Dirty ID sensor • Poor connection of connector • Defective ID sensor • Poor cleaning
• Remedy: 1. Clean the ID sensor. 2. Check if the sensor connector is properly connected. 3. Replace the ID sensor. 4. Check the drum cleaning unit. [ Signal Check ] • ID sensor LED: CN216-B7 or TP103 on I/O control board • ID sensor 1 (K ): CN216-B8 or TP188 on I/O control board / TP115 on main control board. • ID sensor 2 ( CMY): CN216-B9 or TP187 on I/O control board / TP114 on main control board.

• Code: SC387
• Description: Drum potential error - Timing - During initial process control check or interval (number of copies) process control self check - Condition - While the revolver unit returns to the home position, the following condition is detected. VD < VG – 200V VD > VG + 200V
• Causes: • Uneven charge • Deteriorated drum • Defective potential sensor
• Remedy: 1. Clean the charge unit or replace the charge wire and grid plate. 2. Reinstall the drum unit. 3. Check the drum counter (SP 7-803) and replace the drum if necessary. 4. Replace the potential sensor.

• Code: SC400
• Description: Image transfer belt bias error - Timing - While the image transfer belt bias is ON - Condition - The feedback voltage is 4.8V or higher, or PWM value is 50% or higher for 500ms continuously.
• Causes: • Poor connection of connectors • Defective high voltage supply board (T1/PCC/BR) • Defective I/O control board • Defective main control board
• Remedy: 1. Check if the connectors of high voltage cable and trigger lines are properly connected on the high voltage supply board, I/O control board, and main control board. 2. Replace the high voltage supply board (T1/PCC/BR). 3. Replace the I/O control board. 4. Replace the main control board. [ Signal Check ] • Feedback signal: CN209-9, TP264, or CN211-A4 on I/O control board / CN302-A6 or TP106 on main control board. • PWM: CN209-10 or TP272 on I/O control board.

• Code: SC401
• Description: Image transfer belt motor lock - Timing & Condition - • The feedback signal from the motor is still out of range 2 seconds after the trigger signal is sent. • The feedback signal becomes out of range for 2 seconds while the trigger signal is ON.
• Causes: • Defective image transfer belt motor • Defective image transfer belt motor drive board • Mechanical problem (drive transmission)
• Remedy: 1. Check if the connectors on the image transfer belt drive board (CN740 and 741) and I/O control board (CN220) are properly connected. 2. Check the harnesses are damaged. 3. Replace the image transfer belt motor control board. 4. Replace image transfer belt motor. 5. Check if anything causes the load of the belt motor to be increased. [ Signal Check ] • Motor OK: CN220-A2 or TP153 on the I/O control board