Bizhub c454 repeat yellow image

[bobdee]

Re: Bizhub c454 repeat yellow image

Does this happen on other color copies?

Thanks. Yes, it does to colour Text and images and it's only Yellow that causes that

[bobdee]

Re: Bizhub c454 repeat yellow image

Definitely check yellow development unit as others have suggested, but I was thinking along the same lines as Toxic, that there might by an issue with the yellow erase lamps.

Ok, I will check both developer unit and the erase lamp of the Yellow.

[tsbservice]

Re: Bizhub c454 repeat yellow image

Please Thanks for your concern. If I may ask, what causes the developer to overtone??

Old developer material and compatible toner(I suppose without added developer in it).
As for erase leds(lamp) you can trick the machine with front door open and WTB removed and whatch for it.

[bobdee]

Re: Bizhub c454 repeat yellow image

Old developer material and compatible toner(I suppose without added developer in it).
As for erase leds(lamp) you can trick the machine with front door open and WTB removed and whatch for it.

Thanks, I i will check and see

[romario]

Re: Bizhub c454 repeat yellow image

I am using Konica Minolta Bizhub C45. The Machine works correctly until recently the yellow keep repeat image. I have tried the Transfer Belt in other machine and it works fine. When I swapped Yellow and Cyan Drum Units, the yellow Image still keep repeating itself whiles the Yellow Drum Unit Prints correctly at the Cyan Slot.

Attached is a copy of an envelope printed by the printer.

if you change the drum unit Y to the C and the fault remains in the Y. Just change the development unit Y. or developer And that has to solve your problem

[blackcat4866]

Re: Bizhub c454 repeat yellow image

... If I may ask, what causes the developer to overtone??

That's a great question. And there are a lot of answers:

1) Underuse: If you're running 95% monochrome/5% color, the color developers are just sitting there unstirred for long periods of time. The toner settles out of the developer mix. When you do decide to make a color print, it takes a while to get the developer particles charged back up and all the toner stirred back in. During that process, the machine is adding more toner.

2) Generic toner: Electrically, generic toner does not always respond exactly the same as genuine toner. So when the correct amount of generic toner is mixed into the developer, it doesn't always respond to the toner sensor the same way, so it just keeps adding toner to try to get the toner sensor up to 6%.

3) Contamination: Basically the same effect as generic toner. Endusers that use a very poor quality of paper (very high dust content), or in an environment that has a very high level of airborne contamination (like a grindstone manufacturing plant or an iron foundry), that airborne contamination ends up in the developing unit. And if that contamination has magnetic or electrical properties it changes the way the toner sensor reads. Paper dust does not have magnetic or electrical properties, but displaces toner, and leaves light areas (paper dust won't make up a visible latent image).

4) Developer is worn out: When the manufacturer calculates the developer yield it's based on ~4% image fill of each color, and so many color pages. If your color pages are, say 20%, you'll make 1/5th the number of pages. You probably do not know the exact image fill of every color page that you've printed.

In the end though this is all just interesting conversation. Knowing it does not change the need to order a yellow developing unit. =^..^=

[BillyCarpenter]

Re: Bizhub c454 repeat yellow image

That's a great question. And there are a lot of answers:

1) Underuse: If you're running 95% monochrome/5% color, the color developers are just sitting there unstirred for long periods of time. The toner settles out of the developer mix. When you do decide to make a color print, it takes a while to get the developer particles charged back up and all the toner stirred back in. During that process, the machine is adding more toner.

2) Generic toner: Electrically, generic toner does not always respond exactly the same as genuine toner. So when the correct amount of generic toner is mixed into the developer, it doesn't always respond to the toner sensor the same way, so it just keeps adding toner to try to get the toner sensor up to 6%.

3) Contamination: Basically the same effect as generic toner. Endusers that use a very poor quality of paper (very high dust content), or in an environment that has a very high level of airborne contamination (like a grindstone manufacturing plant or an iron foundry), that airborne contamination ends up in the developing unit. And if that contamination has magnetic or electrical properties it changes the way the toner sensor reads. Paper dust does not have magnetic or electrical properties, but displaces toner, and leaves light areas (paper dust won't make up a visible latent image).

4) Developer is worn out: When the manufacturer calculates the developer yield it's based on ~4% image fill of each color, and so many color pages. If your color pages are, say 20%, you'll make 1/5th the number of pages. You probably do not know the exact image fill of every color page that you've printed.

In the end though this is all just interesting conversation. Knowing it does not change the need to order a yellow developing unit. =^..^=

That's a very detailed explanation. I enjoyed reading it.

[JasonSBE]

Re: Bizhub c454 repeat yellow image

I had a very similar issue on a C658 recently. I diagnosed it by swapping drums first, then testing the developer, then swapping the erasure lamp between the color affected(in my case cyan) and another color. None of those things took care of it, so I replaced the FRB board. Apparently the connector wasn't powering the erasure lamp for cyan because that fixed it.

edit:

Just realized that this was a thread from a couple years ago. I'll leave my reply in case it's helpful for someone down the road.

[Hansoon]

Re: Bizhub c454 repeat yellow image

And I just had it these days. Also with yellow. Resetting the yellow DevUnit cured it for the moment until I make a fresh unit next week.

Reread Cat's explanation and am impressed once again....., as always......

Hans