C4501 (bizhub 950i/850i)
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Contents
| Trouble type | C4501: Laser malfunction |
| Rank | B |
| Trouble detection condition | – SOS signal is not detected even after the lapse of a given period of time after starting the laser output. – SOS signal is not detected for a given period of time during printing or IDC sensor adjustment. |
| Trouble isolation | – |
| Relevant electrical parts | – PH unit – PH relay board (PHRYB) – CPU board (CPUB) – Base board (BASEB) |
Procedure
- Check the connector between the PH unit-PHRYB CN8 for proper connection and correct as necessary.
- Check CPUB for proper installation and correct as necessary.
- Replace the PH unit.
- PHRYB IC5 conduction check.
- Replace PHRYB.
- Replace CPUB.
- Replace BASEB.