• Code: C2557
• Description: Abnormally low toner density detected black TCR sensor
  • TC ratio in the developing machine, which is determined by toner replenishing amount control mechanism, is 4 % or less for a given number of times consecutively.
• Remedy: 1 M3 operation check (At this time, IU must be non-installation.) 2 Reinstall imaging unit. 3 Reinstall toner cartridge. 4 Change imaging unit /K. 5 Change PRCB.

• Code: C2558
• Description: Abnormally high toner density detected black TCR sensor
  • TC ratio in the developing machine, which is determined by toner replenishing amount control mechanism, is 11 % or more for a given number of times consecutively. • When the connector of the TCR sensor is disconnected.
• Remedy: 1 Reinstall imaging unit. 2 Reinstall toner cartridge. 3 Change imaging unit. 4 Change PRCB.

• Code: C2559
• Description: Cyan TCR sensor adjustment failure
  • TCR sensor automatic adjustment does not function properly, failing to adjust to an appropriate value.
• Remedy: 1 Reinstall imaging unit. 2 Change imaging unit. 3 Change PRCB.

• Code: C255A
• Description: Magenta TCR sensor adjustment failure
• Remedy: 1 Reinstall imaging unit. 2 Change imaging unit. 3 Change PRCB.

• Code: C255B
• Description: Yellow TCR sensor adjustment failure
• Remedy: 1 Reinstall imaging unit. 2 Change imaging unit. 3 Change PRCB.

• Code: C255C
• Description: Black TCR sensor adjustment failure
• Remedy: 1 Reinstall imaging unit /K. 2 Change imaging unit /K. 3 Change 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. • The machine detects that the service EEPROM board is not loaded in position.
• Remedy: 1 Check the connector (CN23PRCB) on PRCB, the connector (CN1SV ERB) on SV ERB, and the harness between the boards for proper connection and correct as necessary. 2 Change PRCB 2.1. 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.) 2.2. Update the PRCB firmware. 2.3. After completing the firmware update, turn OFF and ON the main power switch and check to see that warm-up is started. Make sure that malfunction codes other than C2650 or improper IU/TC placement is not detected. 4. When the trouble cannot be solved, reinstall the removed PRCB to the original board. NOTE • When taking the above steps, check whether PRCB is defective or not without replacing the SV ERB. 3 Change SV ERB 3.1. Replace the current SV ERB with a new one. 3.2. Turn ON the main power switch and check to see that warm-up is started. (One minute is spent to prepare the new SV ERB for use. During the period, the control panel backlight stays off.) Make sure that malfunction codes other than C2650 or improper IU/TC placement is not detected. 3. Make the specified readjustments. 4 If the above actions do not solve the problem, contact KMBT.

• Code: C2651
• Description: EEPROM access error (IU C)
  • An error was found when reading or writing data. • The error was found when reading out the counter value.
• Remedy: 1 Clean the connection between the imaging unit and the machine if dirty. 2 Reinstall imaging unit. 3 Check the harness for proper connection and correct as necessary. 4 Change imaging unit. 5 Change PRCB.