Bizhub C454e with K Imaging issues

[L0rdC]

So I managed to get a healthy bizhub C454 that I can use to test against the one that is giving me problems. I took the brand new developing unit out of the problematic machine and put it in the known good machine. Before I swapped the units, I checked level 1 history on the problematic machine, this is what I found...
Attachment 54025

The TCR Level for K was showing 7.71%, but the image was so light that it was presenting as if there was little to no toner in the developer.

The good machine was showing the following...

Attachment 54026

K Density at 5.8%. Image quality was as expected.

After swapping the developers, the known good machine showed a TCR density of 0.00%. I ran the manual toner add routine a couple of times and the density got up to an acceptable level. Print quality was good.

The problematic machine showed the TCR density up over 19%

Attachment 54027

All of the warnings for the stabilizer failing and for the IDC sensors went away. However, the machine will code out due to abnormally high density and will not add toner so the issue will not be resolved. I don't know what other components could be causing the machine to read such a faulty TCR density level. I put in a ticket with Konica and covered all the parts that have been replaced and all the troubleshooting that has been done. All they could come with was to replace some of the connectors on the HV board(Specifically the HV and DV contacts).

Did you change the HV board on the left of the machine? try to change it, a technician once told me that the controller board and TCR were related and that he had had reading problems as is happening to you

[JasonSBE]

Did you change the HV board on the left of the machine? try to change it, a technician once told me that the controller board and TCR were related and that he had had reading problems as is happening to you

The board on the left side? Do you mean the DC power supply? I have not changed that but I was considering it.

[L0rdC]

The board on the left side? Do you mean the DC power supply? I have not changed that but I was considering it.

PH board, sorry...

[tmmdmmm]

PH board, sorry...

Reading the theory again I can't see how this would be the case, but we are in the F around stage. I'd try that and the PH one at a time since the PH was not swapped

[romario]

This is an odd one for me. Customer put in service request stating that machine was giving them poor image quality. I had them print the built-in demo page and send an image to me. The black portion of the image was not being put on the paper, instead there was some residue on the page that looked like developer. I grabbed a brand new IU-512K and DR-512k and went to the site. TCR density for CMY were all in the expected range, but K was a 0.00%. Replaced the drum and developer as a set(Drum was at end of life, and I've seen issues where these machines will bleed out a developer if you have an old drum, so I figured it was worth doing). Printed some test patterns, and the image was very light. TCR density read normal.

I decided to take the machine back to my shop to work on it. First thing I did was try another developing unit. This time I pulled one out of another machine. Print quality was good, but TCR density showed very high.... like almost 19%. Naturally, the machine coded out every 20 pages or so. I ran some full density half tones to see if the level would drop and the machine would level out, but by the time the TCR sensor was detecting density down to around 12% copy quality was awful. Next thing I tried was changing out the board the developers plug into(A7PUH00500 FRB Board). Flashed the firmware to latest base, and still having the same issues.

Never seen anything like this issue, was hoping for some insite.

Hello, I have had these problems several times, 1) that the black toner does not stick to the paper, this is a toner problem to repair, I had to empty the entire hopper CHANGE TONER, change developer, 2) when I try to exchange the unit of developed by another machine, the reading reached 16%, what I did was put the same reader of the revaldo unit... the first thing I would do in your case is to empty the hopper, change the toner, change the developer because it is already contaminated and you will see that it will work for you

[JasonSBE]

PH board, sorry...

Is that the little board with the two ribbon cables going to it? I just replaced the DC power supply followed by that board. Same issues.......

[tsbservice]

Is that the little board with the two ribbon cables going to it? I just replaced the DC power supply followed by that board. Same issues.......

You continue erroneous troubleshooting... anyway good luck with that.

[techsxge]

You continue erroneous troubleshooting... anyway good luck with that.

I mean as long as he earns enough to not ruin his company, who cares? If he sends them back to KM what he took out the machines we get some great B-Ware soon

[techsxge]

I still vouch for the fusing unit.

REASON: Its not the Drum, its not the Developer. Its not the Transfer Unit. Op changed multiple boards that would somehow control printing. The only thing that could still affect Image is Fusing Unit. Or Toner bottle.


You can check very easily if i am right: Do some prints. Is it still worse? Fusing Unit / Toner. Is it better? Scanner.

[tmmdmmm]

I still vouch for the fusing unit.

REASON: Its not the Drum, its not the Developer. Its not the Transfer Unit. Op changed multiple boards that would somehow control printing. The only thing that could still affect Image is Fusing Unit. Or Toner bottle.


You can check very easily if i am right: Do some prints. Is it still worse? Fusing Unit / Toner. Is it better? Scanner.

His last post with the two machines and TCR values prove its a detection issue, I'm just not sure why at this point The image quality is purely a biproduct of the detection issue.

Machine 1 Dev 1: Shows TCR 7.71 despite realistically being 0%.
Machine 2 Dev 2: Shows TCR as 5.8 which is correct

Machine 1 Dev 2: Shows TCR 19% despite being 5.8
Machine 2 Dev 1: Shows TCR as 0%, which is correct.

Machine 1 is not properly detecting is actual TCR

But it's still a 5 minute test, go ahead and entertain the fuser route