Bizhub c550 error c4501

[Accracin]

About to pull my hair out on this one lol. Any help is much appreciated!

Error c4501

Ok got this unit had another error for the scanner, i could bypass it and it would print fine. I narrowed it down to the power board and replaced it.
The machine was moved while waiting for the powerboard. Put new board in and got the c4501. It will scan now but that error comes up before it will print.
I put old power board back in machine now it has the scanner error and c4501. Put new back in , took macine mostly down checked all connections and wiring. Unplugged the adf. Still no luck so i replaced the ph unit. Still getting same code. Anyone have any suggestions?

[copyman]

All I can think of is those ribbon cables for laser unit. If they are the same as a few other Kon/Min PH laser units I've changed the ribbon cables were tricky to seat properly. I would look at those again, especially if they have the plastic clip that locks the cable in.

[tsbservice]

If you already replaced DC power supply and PH unit, check following ICPs:

- ICP6 on the PH relay board (REYB/PH) is open.
Replace REYB/PH

- ICP22 on the Printer control board (PRCB) is open.
Replace the PRCB

Note: If ICP22 is OPEN, it is recommended to replace the PH unit and the Printer Control Board at the same time.

[Accracin]

Thanks so much! I checked icp6 on the ph relay board it is good. I cannot find icp22 on the prcb found 21 23 26. is it by chance on the back of the board? I have rechecked the ribbon cables also. Tha ks so much for the help

- ICP6 on the PH relay board (REYB/PH) is open.
Replace REYB/PH

- ICP22 on the Printer control board (PRCB) is open.
Replace the PRCB

[Synaux]

Thanks so much! I checked icp6 on the ph relay board it is good. I cannot find icp22 on the prcb found 21 23 26. is it by chance on the back of the board? I have rechecked the ribbon cables also. Tha ks so much for the help

- ICP6 on the PH relay board (REYB/PH) is open.
Replace REYB/PH

- ICP22 on the Printer control board (PRCB) is open.
Replace the PRCB

Do you have the Service Manual? If you need it, make a small (or large) contribution and I will send it to you, or someone else will.
I do not have a PRCB nearby to look at, but I found it in the schematics.

Also, if memory serves, the REYB/PH has 3 ICPs. I have had three different boards blow the same ICP (cracked it). I do not remember which ICP exactly, but I ended up retiring the machine - never found the cause. I am pretty sure I used the PH in another machine and have the PRCB in a box...somewhere with a cross-your-fingers-label on it.