C2557 (bizhub 754e/654e)
Contents
| Trouble type | Abnormally low toner density detected black TCR sensor |
| Trouble code | C2557 |
| Rank | B |
| Detection timing | 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 (PZS/K) • Toner supply motor/K (M12) • Toner cartridge motor /CK (M14) • Printer control board (PRCB) |
(2)Procedure
| Step | Action | Control signal | Location of electrical components |
| 1 | Perform image troubleshooting procedure if image density is low. | – | – |
| 2 | Check the connector between M12-relay CN258-PRCB CN3 for proper connection, and correct as necessary. | – | – |
| 3 | Check the connector between M14-relay CN321-relay CN428-PRCB CN4 for proper connection, and correct as necessary. | – | – |
| 4 | Check the connector of M12 and M14 for proper drive coupling and correct as necessary. | – | – |
| 5 | M12 operation check(At this time, developing/drum unit must be non-installation.) | PRCB CN3-1 to 4 | 23-C |
| 6 | M14 operation check | PRCB CN4-1 to 4 | 3-K |
| 7 | Replace M12 and M14 | – | – |
| 8 | Reinstall developing unit | – | – |
| 9 | Reinstall toner cartridge | – | – |
| 10 | If the toner empty sensor and its surroundings inside the sub hopper are dirtied with toner, clean them. | – | – |
| 11 | Replace the developing unit (Part# A2X203D) | – | – |
| 12 | PRCB ICP23 or ICP24 conduction check | – | – |
| 13 | Replace PRCB. (Part# A55VH00105) | – | – |
- Link to the wiring diagram (N.1. bizhub 754e/654e)
Please search Knowledge Base articles and Bulletins as they may contain relevant information and updated Part information such as Part numbers.
K.3.7.12 (Link to the Field Service Manual)