C2557 (bizhub C759/C659)
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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 lower 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/K -Toner cartridge/K -Toner empty sensor/K (PZS/K) -Toner supply motor/K (M12) -Toner cartridge motor /CK (M14) -Process drive board (PDB) -MFP board (MFPB) |
Procedure
- Perform image troubleshooting procedure if image density is low.
- Reinstall developing unit/K.
- Reinstall toner cartridge/K.
- Check the connector between M12-relay CN258-PDB CN8 for proper connection and correct as necessary.
- Check the connector between M14-relay CN321-relay CN428-PDB CN7 for proper connection and correct as necessary.
- Check the connector of M12, M14 for proper drive coupling and correct as necessary.
- Check the connector between PZS/K-relay CN248-relay CN265-MFPB CN4E for proper connection and correct as necessary.
- PZS/K I/O check, sensor check
- Control signal: MFPB CN4E<B>-12 (ON)
- Location of electrical component: 17-C
- M12 operation check (At this time, developing/drum unit must be non-installation.)
- Control signal: PDB CN8-13 to 16
- Location of electrical component: 16-X
- M14 operation check
- Control signal: PDB CN7-1 to 4
- Location of electrical component: 17-P
- Replace M12. (Part# A00JM12100)
- Replace M14. (Part# 9314130021)
- If the toner empty sensor and its surroundings inside the sub hopper are dirtied with toner, clean them.
- Replace the developing unit/K. (Part# A9K703D)
- PDB F1 or F2 conduction check
- Replace PDB. (Part# A8JEH00400)
- Replace MFPB. (Part# A8JEH02002)
L.3.9.14 (Link to the Field Service Manual)