• Code: C225C
• Description: K PC drum motor’s turning at abnormal timing • The motor lock signal remains LOW for a predetermined continuous period of time while the motor remains stationary.
• Causes: K PC drum motor (M18) Printer control board (PRCB)
• Remedy: 1 Check the M18 connector for proper connection and correct as necessary. 2 Check the M18 connector for proper drive coupling and correct as necessary. 3 Check the PRCB connector for proper connection and correct as necessary. 4 M18 operation check PRCB CN35-10 (REM) PRCB CN35-13 (LOCK) K-2 5 Change M18 6 PRCB ICP14 conduction check 7 Change PRCB

• Code: C2350
• Description: Toner suction fan motor’s failure to turn • The motor lock signal remains HIGH for a predetermined continuous period of time while the motor is turning.
• Causes: Toner suction fan motor (FM7) Printer control board (PRCB)
• Remedy: 1 Check the FM8 connector for proper connection and correct as necessary. 2 Check the fan for possible overload and correct as necessary. 3 FM7 operation check PRCB CN15-1 (REM) PRCB CN15-3 (LOCK) K-10 4 Change FM7 5 PRCB ICP6 conduction check 6 Change PRCB

• Code: C2353
• Description: IU cooling fan motor’s failure to turn • The motor lock signal remains HIGH for a predetermined continuous period of time while the motor is turning.
• Causes: IU cooling fan motor (FM15) PH relay board (REYB/PH) Printer control board (PRCB)
• Remedy: 1 Check the FM15 connector for proper connection and correct as necessary. 2 Check the fan for possible overload and correct as necessary. 3 FM15 operation check REYB/PH CN5-1 (REM) REYB/PH CN5-3 (LOCK) A to B-6 4 Change FM15 5 REYB/PH ICP1 conduction check 6 Change REYB/PH 7 Change PRCB

• Code: C2354
• Description: Rear side cooling fan motor’s failure to turn • The motor lock signal remains HIGH for a predetermined continuous period of time while the motor is turning.
• Causes: Rear side cooling fan motor (FM16) Printer control board (PRCB)
• Remedy: 1 Check the FM16 connector for proper connection and correct as necessary. 2 Check the fan for possible overload and correct as necessary. 3 FM16 operation check PRCB CN18-2 (REM) PRCB CN18-3 (LOCK) C-12 to 13 4 Change FM16 5 PRCB ICP7 conduction check 6 Change PRCB

• 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.
• Causes: Developing unit Toner cartridge Toner empty sensor/K (PZS/K) Toner supply motor/K (M12) Toner cartridge motor C/K (M14) Printer control board (PRCB)
• Remedy: 1 Perform image troubleshooting procedure if image density is low. 2 M12 operation check (At this time, developing/drum unit must be non-installation.) PRCB CN19-13 to 16 C-20 3 M14 operation check PRCB CN20-9 to 12 K-8 4 Reinstall developing unit 5 Reinstall toner cartridge 6 If the toner empty sensor and its surroundings inside the sub hopper are dirtied with toner, clean them. 7 Change developing unit 8 Change PRCB.

• Code: C2558
• Description: Abnormally high toner density detected black TCR sensor • TC ratio in the developing unit, which is determined by toner replenishing amount control mechanism, is a predetermined value or more for a given number of times consecutively.
• Causes: Developing unit Toner cartridge Sub hopper unit Printer control board (PRCB)
• Remedy: 1 Reinstall developing unit 2 Reinstall toner cartridge 3 Change developing unit 4 PRCB ICP17 conduction check 5 Change PRCB 6 Change sub hopper unit

• Code: C255C
• Description: Black TCR sensor adjustment failure • TCR sensor automatic adjustment does not function properly, failing to adjust to an appropriate value.
• Causes: Developing unit Printer control board (PRCB)
• Remedy: 1 Reinstall developing unit 2 Change developing unit 3 PRCB ICP17 conduction check 4 Change PRCB

• Code: C2564
• Description: Black TCR sensor failure • Alarm signals for a TCR sensor are detected more than the predetermined number of times. This detection is used for detecting disconnection of TCR sensor connector.
• Causes: Developing unit Printer control board (PRCB)
• Remedy: 1 Reinstall developing unit 2 Check the harness from developing unit to PRCB for proper connection and correct as necessary. 3 Change developing unit 4 PRCB ICP2 conduction check 5 Change PRCB