• Code: C3922
• Description: Fusing sensor wire breaks detection (Edge of the heating roller)
  After a predetermined period of time after the warm-up stage is started, the heating roller thermistor/1 (TH1) voltage does not decrease by predetermined steps (temperature rise) within a predetermined period of time.
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the open/close operation of the upper right door. 3 Check the fusing unit and PRCB for proper connection and correct or change as necessary. 4 Replace the fusing unit. 5 Replace PRCB.

• Code: C3925
• Description: Fusing sensor wire breaks detection (Center of the heating roller)
  After a predetermined period of time after the warm-up stage is started, the heating roller temperature sensor (TEMS) voltage does not increase by predetermined steps (temperature rise) within a predetermined period of time.
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the open/close operation of the upper right door. 3 Check the fusing unit and PRCB for proper connection and correct or change as necessary. 4 Replace the fusing unit. 5 Replace PRCB.

• Code: C3926
• Description: Fusing sensor wire breaks detection (Middle of the heating roller)
  • After a predetermined period of time after the warm-up stage is started, the heating roller thermistor/2 (TH2) voltage does not decrease by predetermined steps (temperature rise) within a predetermined time. • When a temperature detected by the heating roller thermister/1 (TH1) is compared with the temperature detected by the heating roller thermister/2 (TH2) to find out that the difference exceeded the predetermined temperature.
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the open/close operation of the upper right door. 3 Check the fusing unit and PRCB for proper connection and correct or change as necessary. 4 Replace the fusing unit. 5 Replace PRCB.

• Code: C4101
• Description: Polygon motor rotation trouble
  • The polygon motor fails to turn stably even after the lapse of a given period of time after activating and changing rotation speed the polygon motor. • Motor lock signal detects HIGH for a given period time consecutively during the polygon motor is rotating.
• Remedy: 1 Check the connector between PH unit-FRB CN17 for proper connection and correct as necessary. 2 Replace the PH unit. 3 FRB fuse conduction check 4 Replace FRB. 5 Replace PRCB.

• Code: C4501
• Description: Laser malfunction
  • SOS signal is not detected even after the lapse of a given period of time after starting the laser output. • SOS signal is not detected for a given period of time during printing or IDC sensor adjustment.
• Remedy: 1 Check the connector between PH unit-PRCB CN24 for proper connection and correct as necessary. 2 Replace the PH unit. 3 Replace PRCB.

• Code: C4801
• Description: Main unit board failure
  MFP detects simultaneous replacement of multiple boards.
• Remedy: 1 Reinstall the old PRCB. 2 Back up data. 1. Call the Service Mode to the screen. 2. Call the Enhanced Security to the screen. 3. Touch [Engine Data Backup]. 2. Touch [Engine Data Save mode], and press the Start key. 3. Select [Yes], and press the Start key again. 4. Check that the result “OK” appears. 3 Replace PRCB Turn OFF the main power switch and replace the current PRCB with a new one. (When using a PRCB of another machine in service, be sure to use a PRCB installed in the same model.) 4 Restore back up data. 1. Turn ON the main power switch. 2. Check that the trouble code “C4802” appears and then display service mode. 3. Call the Enhanced Security to the screen. 4. Touch [Engine Data Backup]. 5. Touch [Engine Data Load mode], and press the Start key. 6. Select [Yes], and press the Start key again. 7. Check that the result “OK” appears. 8. Turn OFF the main power switch and turn it ON again more than 10 seconds after. 5 Update the PRCB firmware. 6 If the above actions do not solve the problem, contact KMBT.

• Code: C4802
• Description: Main unit backup data miscompare
  The replacement of the printer control board is detected.
• Remedy: 1 1.1. Check that the trouble code “C4802” appears and then display service mode.1. 2. Call the Enhanced Security to the screen. 1.3. Touch [Engine Data Backup]. 1.4. Touch [Engine Data Load mode], and press the Start key. 1.5. Select [Yes], and press the Start key again. 1.6. Check that the result “OK” appears. 1.7. Turn OFF the main power switch and turn it ON again more than 10 seconds after. 2 Update the PRCB firmware. 3 If the above actions do not solve the problem, contact KMBT.

• Code: C5102
• Description: Transport motor’s failure to turn
  The motor lock signal remains HIGH for a predetermined continuous period of time while the motor remains stationary.
• Remedy: 1 Check the connector between M1-PRCB CN31 for proper connection and correct as necessary. 2 Check M1 for proper drive coupling and correct as necessary. 3 M1 operation check PRCB CN31-2 (REM) PRCB CN31-5 (LOCK). 4 Replace M1. 5 Replace PRCB.