• Code: C2554
• Description: Abnormally high toner density detected magenta TCR sensor
  • TC ratio in the developing machine, which is determined by toner replenishing amount control mechanism, is 12 % or more for a given number of times consecutively.
• Remedy: 1 Clean the TCR sensor window on the underside of the imaging unit if dirty 2 Reinstall imaging unit. 3 Change imaging unit. 4 Change MFPB. 5 Change PRCB.

• Code: C2555
• Description: Abnormally low toner density detected yellow TCR sensor
  • TC ratio in the developing machine, which is determined by toner replenishing amount control mechanism, is 5 % or less for a given number of times consecutively.
• Remedy: 1 Perform image troubleshooting procedure if image density is low. 2 Clean the TCR sensor window on the underside of the imaging unit if dirty 3 M6, M7 operation check MFPB CNDM2-10 to 13 (M6) MFPB CNDM3-10 to 13 (M7) C-20 C-21. 4 Reinstall imaging unit. 5 Change imaging unit. 6 Change MFPB. 7 Change PRCB.

• Code: C2556
• Description: Abnormally high toner density detected yellow TCR sensor
  • TC ratio in the developing machine, which is determined by toner replenishing amount control mechanism, is 12 % or more for a given number of times consecutively.
• Remedy: 1 Clean the TCR sensor window on the underside of the imaging unit if dirty 2 Reinstall imaging unit. 3 Change imaging unit. 4 Change MFPB. 5 Change PRCB

• 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 Perform image troubleshooting procedure if image density is low. 2 Clean the TCR sensor window on the underside of the imaging unit if dirty 3 M7 operation check MFPB CNDM3-10 to 13 C-21 4 Reinstall Imaging unit. 5 Change imaging unit /K. 6 Change MFPB. 7 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 12 % or more for a given number of times consecutively.
• Remedy: 1 Correct the TCR connection on the underside of the imaging unit if faulty. 2 Reinstall imaging unit. 3 Change imaging unit. 4 Change MFPB. 5 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 Clean the TCR sensor window on the underside of the imaging unit if dirty 2 M6, M7 operation check MFPB CNDM2-10 to 13 (M6) MFPB CNDM3-10 to 13 (M7) C-20 C-21. 3 Reinstall imaging unit. 4 Change imaging unit. 5 Change MFPB. 6 Change PRCB.

• Code: C255A
• Description: Magenta TCR sensor adjustment failure
• Remedy: 1 Clean the TCR sensor window on the underside of the imaging unit if dirty 2 M6, M7 operation check MFPB CNDM2-10 to 13 (M6) MFPB CNDM3-10 to 13 (M7) C-20 C-21. 3 Reinstall imaging unit. 4 Change imaging unit. 5 Change MFPB. 6 Change PRCB.

• Code: C255B
• Description: Yellow TCR sensor adjustment failure
• Remedy: 1 Clean the TCR sensor window on the underside of the imaging unit if dirty 2 M6, M7 operation check MFPB CNDM2-10 to 13 (M6) MFPB CNDM3-10 to 13 (M7) C-20 C-21. 3 Reinstall imaging unit. 4 Change imaging unit. 5 Change MFPB. 6 Change PRCB.