• Code: C2557
• Description: Abnormally low toner density detected black TCR sensor
  When sampling data is determined in TC ratio calculation control, TCR sensor output is higher than a predetermined value for a predetermined number of times in a row even though there is toner in the sub hopper
• Remedy: 1 Perform image troubleshooting procedure if image density is low. 2 Reinstall developing unit. 3 Reinstall toner cartridge. 4 Check the connector between developing unit-FRB CN13, CN14, CN15, CN16 for proper connection and correct as necessary. 5 Check the connector between FRB CN1, CN3-PRCB CN7, CN9 for proper connection and correct as necessary. 6 M10 operation check M10 PRCB CN14-13 to 16 20-C 7 M6, M7. M8, M9 operation check PRCB CN14-13 to 16 (M6) PRCB CN14-9 to 12 (M7) PRCB CN14-5 to 8 (M8) PRCB CN14-1 to 4 (M9) 19 to 20-C. 8 If the toner empty sensor and its surroundings inside the sub hopper are dirtied with toner, clean them. 9 Replace the developing unit - - 10 Replace FRB. 11 PRCB ICP21, ICP40, ICP41, ICP44, ICP46 conduction check. 12 Replace PRCB.

• Code: C2558
• Description: Abnormally high toner density detected black TCR sensor
  The TC ratio of the toner determined by the toner replenishment control is detected to be the predetermined value or over for consecutive times.
• Remedy: 1 Reinstall developing unit. 2 Reinstall toner cartridge. 3 Check the connector between developing unit-FRB CN13, CN14, CN15, CN16, CN10 for proper connection and correct as necessary. 4 Check the connector between FRB CN1, CN3-PRCB CN7, CN9 for proper connection and correct as necessary. 5 Replace the developing unit. 6 Replace FRB. 7 Replace PRCB.

• Code: C255C
• Description: Black TCR sensor adjustment failure
  TCR sensor automatic adjustment does not function properly, failing to adjust to an appropriate value.
• Remedy: 1 Reinstall developing unit. 2 Check the connector between developing unit-FRB CN13, CN14, CN15, CN16 for proper connection and correct as necessary. 3 Check the connector between FRB CN1, CN3-PRCB CN7, CN9 for proper connection and correct as necessary. 4 M10 operation check PRCB CN14-17 to 20 20-C 5 M6, M7, M8, M9 operation check PRCB CN14-13 to 16 (M6) PRCB CN14-9 to 12 (M7) PRCB CN14-5 to 8 (M8) PRCB CN14-1 to 4 (M9) 19 to 20-C. 6 Replace the developing unit. 7 Replace FRB. 8 PRCB ICP21, ICP40, ICP43, ICP44, ICP46 conduction check. 9 Replace PRCB.

• Code: C2564
• Description: Black TCR sensor failure
  TCR sensor automatic adjustment does not function properly, failing to adjust to an appropriate value.
• Remedy: 1 Reinstall developing unit. 2 Check the connector between developing unit-FRB CN13, CN14, CN15, CN16 for proper connection and correct as necessary. 3 Check the connector between FRB CN1, CN3-PRCB CN7, CN9 for proper connection and correct as necessary. 4 Replace the developing unit. 5 Replace FRB. 6 Replace PRCB.

• Code: C2650
• Description: Main backup media access error
  • The re-written data, which has been read out, checked and founded as error, is read out again and found as error. • The error was found when reading out the counter value. • MFP detects that the SSD board is not mounted.
• Remedy: 1 Check the connector from SSDB to MFPB for proper connection and correct as necessary. 2 Check the harness from MFPB to PRCB for proper connection and correct as necessary. 3 Replace MFPB. 4 Replace PRCB. 4.1. Check that the trouble code “C4802” appears and then display service mode. 4.2. Call the Enhanced Security to the screen. 4.3. Touch [Engine Data Backup]. 4.4. Touch [Engine Data Load mode], and press the Start key. 4.5. Select [Yes], and press the Start key again. 4.6. Check that the result “OK” appears. 4.7. Turn OFF the main power switch and turn it ON again more than 10 seconds after. 4.8. Update the PRCB firmware. 4.9. Make the specified readjustments. 5 If the above actions do not solve the problem, contact KMBT.

• Code: C2A14
• Description: Drum unit/K new release failure
  The status with the new unit is not cleared after the new drum unit is set.
• Remedy: 1 Clean the connection between the drum unit and the machine if dirty. 2 Reinstall drum unit. 3 Check the connector between drum unit-FRB CN12 for proper connection and correct as necessary. 4 Check the connector between FRB CN1, CN3-PRCB CN7, CN9 for proper connection and correct as necessary. 5 Replace the drum unit. 6 Replace FRB. 7 Replace PRCB.

• Code: C3101
• Description: Fusing roller separation failure
  • With the fusing roller being retracted, the fusing pressure home sensor (PS38) is not unblocked even after the specified period of time has passed after the fusing pressure motor (M11) started rotating. • With the fusing roller being pressed, the fusing pressure home sensor (PS38) is not blocked even after the specified period of time has passed after the fusing pressure motor (M11) started rotating.
• Remedy: 1 Check the connector between M11-PRCB CN13 for proper connection and correct as necessary. 2 Check the connector between fusing unit-relay CN98, CN99, CN104-PRCB CN5 for proper connection and correct as necessary. 3 PS38 I/O check, sensor check PRCB CN5-12 (ON) 27 to 28-C. 4 M11 operation check PRCB CN13-1 to 4 25-C. 5 Replace M11. 6 Replace the fusing unit. 7 PRCB IC26 conduction check. 8 Replace PRCB.

• Code: C3201
• Description: Fusing motor 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 M3-PRCB CN2 for proper connection and correct as necessary. 2 Check the loading status of the fusing unit drive, and correct the error as necessary. 3 M3 operation check PRCB CN2-9 (REM) PRCB CN2-12 (LOCK) 27-I to J. 4 Replace M3. 5 Replace PRCB.