Bizhub c554e c2551 error and not printing cyan

[Intone]

Customer called with this code which is abnormally low cyan, we went out and ran tcr supply and the machine still continued to throw up the code. toner was low so that was changed and ran tcr again, same code. machine was close to needing developer unit change so we swapped that out next, still code came up. ran stabilizer gradations and tcr again with the code continuing. we then replaced the toner out sensor, at the time of service the cyan is not printing at all on the test chart. code also still comes up. we are leaning toward the front board under the developer and drum units next. the toner bottle is confirmed to be turning. has anyone else encountered anything similar? running down a lot of parts on this one when on earlier machines the fix for these codes was straight forward. any help is greatly appreciated. thank you

[TheBlueOrleans]

Had this happen once. Took me a while to get it.

Could be front side board, but I recommend first running the cyan Toner Hopper fill in the manual toner add, and run the TCR adjust for cyan at least three times.
Power cycle after the third run, return to service mode and check TCR level.
If it is still too low you may need to replace the toner hopper as well as the FSB.

[Intone]

thank you blue, we will try this next

[MVPunisher]

I once had a cyan developing unit that was pulling all the developer out (to the front). Replaced Dev unit, came back. Replaced HV unit with another dev unit, came back. Replaced the drum with the Dev unit and it never came back. Shoulda started with the easier part first.....

[deepdiver]

Had this last week with C284e with black C2557 I think. Extended life settings on. Drum was past life. Dev unit almost past life. Customer replaced black toner no good. I replaced black drum no good so replaced black Dev as well & fixed it. Think it was a combination of drum passed life and Dev almost end of life. Be careful if you are using extended life settings.

[aleksander]

Customer called with this code which is abnormally low cyan, we went out and ran tcr supply and the machine still continued to throw up the code. toner was low so that was changed and ran tcr again, same code. machine was close to needing developer unit change so we swapped that out next, still code came up. ran stabilizer gradations and tcr again with the code continuing. we then replaced the toner out sensor, at the time of service the cyan is not printing at all on the test chart. code also still comes up. we are leaning toward the front board under the developer and drum units next. the toner bottle is confirmed to be turning. has anyone else encountered anything similar? running down a lot of parts on this one when on earlier machines the fix for these codes was straight forward. any help is greatly appreciated. thank you

1. assured that the developing motor (Cyan) work properly.
2. change drum unit C
3. replace PRCB