• Code: 6740
• Description: Abnormally high IGBT2 temperature (IHPWB)
• Causes: Defective IH PWB.
  Defective cooling fan motor.
• Remedy: Defective IH PWB. Replace the IH PWB and check for correct operation.
  Defective cooling fan motor. Replace the IH fan motor.

• Code: 6750
• Description: Abnormally output overcurrent (IHPWB)
• Causes: Defective IH PWB.
  Defective fuser unit.
• Remedy: Defective IH PWB. Replace the IH PWB and check for correct operation.
  Defective fuser unit. Replace the fuser unit.

• Code: 6760
• Description: Abnormally AC input over-current (IHPWB)
• Causes: Defective IH PWB.
• Remedy: Replace the IH PWB and check for correct operation.

• Code: 6770
• Description: Abnormally low electric power (IHPWB)
• Causes: Defective connector cable or poor contact in the connector.
  Defective IH PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable.
  Defective IH PWB. Replace the IH PWB and check for correct operation.

• Code: 6930
• Description: IH coil fan motor error
  The alarm signal was detected for 5 seconds continuously during operation.
• Causes: Defective connector cable or poor contact in the connector.
  Defective cooling fan motor.
  Defective IH PWB
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. IH coil fan motor and engine PWB(YC21)
  Defective cooling fan motor. Replace the IH coil fan motor.
  Defective IH PWB. Replace the IH PWB and check for correct operation.

• Code: 6950
• Description: IH CPU communication error A communication error is detected 3 times in succession.
• Causes: Defective connector cable or poor contact in the connector.
  Defective IH PWB.
  Defective engine PWB.
  
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable.
  Defective IH PWB. Replace the IH PWB and check for correct operation.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 6990
• Description: Fuser unit type mismatch problem
  Absence of the fuser unit is detected.
• Causes: Defective IH PWB.
• Remedy: Replace the IH PWB and check for correct operation.

• Code: 7001
• Description: Toner motor K error
  When the toner motor K is driven, error signal is detected continuously for 1 s.
• Causes: Defective connector cable or poor contact in the connector.
  Defective drive transmission system.
  Defective motor.
  Defective PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Toner motor K and engine PWB(YC8)
  Defective drive transmission system. Check if the rollers and gears rotate smoothly. If not, grease the bushings and gears. Check for broken gears and replace if any.
  Defective motor. Replace the toner motor K.
  Defective PWB. Replace the engine PWB check for correct operation.