C2557 (bizhub 558/458)

Contents

Trouble type	C2557: Abnormally low toner density detected black TCR sensor
Rank	B
Trouble detection condition	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.
Trouble isolation	–
Relevant electrical parts	• Developing unit • Toner cartridge • Toner empty sensor/K (PS31) • Toner cartridge motor/K (M25) • Toner supply motor/K (M6) • Expansion control board (EXCB) • Front side board (FRB) • MFP board (MFPB)

 Procedure

1. Perform image troubleshooting procedure if image density is low.
2. Reinstall the developing unit.
3. Reinstall the toner cartridge.
4. Check the connector between the developing unit-FRB CN13 for proper connection and correct as necessary.
5. Check the connector between FRB CN1, CN3-MFPB CN4E, CN5E for proper connection and correct as necessary.
6. M25 operation check
   • Control signal: MFPB CN28E-4 to 7
   • Location of electrical component: 11-C
7. M6 operation check
   • Control signal: EXCB CN3-4 to 7
   • Location of electrical component: 26-T
8. If the toner empty sensor and its surroundings inside the sub hopper are dirtied with toner, clean them.
9. Replace the developing unit. (Part# A9C803D)
10. Replace FRB. (Part# A9HJH00501)
11. Replace EXCB. (Part# A9HGH00501)
12. MFPB F6E conduction check
13. Replace MFPB. (558 Part# A9HGH02102 / 458 Part# A9HHH02102)

NOTICE

• Link to the wiring diagram (bizhub 558/458)

Please search Knowledge Base articles and Bulletins as they may contain relevant information and updated Part information such as Part numbers.

K.3.11.4 (Link to the Field Service Manual)