Konica C750i and C550i code 255x erros

[pmotard]

Has anyone seen a rash of C255x codes on these models? We have replaced PCU, Developer, expansion board, toner hopper and toner drive assemblies. We can manually tone up the developer and watch the values go to specification. However the codes keep returning. We are working with Konica as we have several i series machines doing this. More times than not it is the black unit throwing the code but we have seen magenta and yellow do same. Some are using the alternate toner (AK) that Konica is sending and some are using OEM toner so we kind of ruled that out. I am wondering if the chip shortage forced some manufacturers to go else where and perhaps we have some bad chips on boards.... any insight would be appreciated.

[allan]

The fact that it returns to value after manual toner add tells me the control is just fine. It could happen with large high coverage jobs but seen that with the C360 machines last. It could very well be your toner.

You need to tone up? Do the values falls below 4%? Or per chance Above 8%?

If the toner clumps up due to moisture or constancy this could happen. Then if the permeability of the toner does not match that of the OEM toner then that could be a reason too.

Run half tones at 255 and watch the density until it errors out. If it errors out with not real change in density I hope I have a tasty hat. Then do something only I would do. Don't tone it up manually but knock the hopper with the but end of your screwdriver with the door open while its running. If it works in that case its the toner that does not move well by its self. Watch the toner bottle rotation while all this is happening to see what happens there.

Then there is firmware before I would opt to change the processor??
Its not out of the range of imagination that HV arching could do this. Had some cases where the TCR value will go to 0% and right back up if say the humidity changes.

If that is not already out there check your altitude.

Does this happen out of the box? Could be that the mix got compacted in the bottom of the dev tank in that case like the C3350i's.

[pmotard]

We have verified the values do go back into range after forcing toner in. In some cases we have run the half tone patterns and watched the values go down and then return to normal. Firmware is up to date. All the things that would normally resolve this on any other unit seem of no use on this model... I will have my guys look harder at the toner supply although we have replaced the hopper as well.

[allan]

We have verified the values do go back into range after forcing toner in. In some cases we have run the half tone patterns and watched the values go down and then return to normal. Firmware is up to date. All the things that would normally resolve this on any other unit seem of no use on this model... I will have my guys look harder at the toner supply although we have replaced the hopper as well.

Does this happen out of the box?

[tsbservice]

Normally I would say toner sub hopper assy but you've replaced it. Do you mean whole thing with sub hopper sensors and leaking white bushings included( like on C224e model)?

[MVPunisher]

I take a lot of pride in my troubleshooting process and understanding "why" things happen.

And I gotta tell ya I am getting destroyed by Toner loading issues at 1 account on 3 different C550is. So I feel your pain and will be following this post.

The issue is that the symptoms and resolutions are not exactly the same each time. Which in turn makes my head spin and re-theorize whats actually happening.

Between the 3 machines my symptoms are:
Machine asking for toner when not empty primarily black
C-255x codes I did have 1 other non black code here at a different acct once, sub hopper fixed.

Between the 3 machines things I have done that have and have not fixed:
-Replaced Toner drive in back, no changes.
-Replaced Sub hopper (has fixed some, and not fixed some)
-Confirmed with my eye balls that both the bottle can turn, and that the sub hopper is conveying.
-Manually turn the bottle with hand , Simultaneously funneling toner into dev unit to trick machine into thinking the bottle loaded fine. Machine not only runs, but runs that ENTIRE bottle before becoming a problem again?! So clearly mechanically the machine is capable of loading toner. Just chooses not to.
-Recently had one where the Dev unit actually fixed it that time. TCR sensor not reporting back properly?

At the end of the day I said the same thing myself the other day. A chip issue on the supplies? A board issue? There is a communication issue somewhere. MULTIPLE times (but not every time) once I got the machine to accept the toner it ran the whole bottle before becoming an issue again. That's logical issue not a mechanical issue? right?

Konica is getting a call from me Monday morning as it has shown its ugly face hard again this week with school season back.

[allan]

Yea if that happen only after new article detection it could very well be logical. Print or capture the management list before and after installing toner and for interest see if it registered the new toner article.

[mojorolla]

Trap_Code_C-Code_C2551.pdf

Trap_Code_C-Code_C2553.pdf

Trap_Code_C-Code_C2555.pdf

[EarthKmTech]

My experiences:

on the c750i series with the large black plastic toner cartridges - it is absolutely essential that these are shaken before installation - the bottle drive coupling is very weak in design and shears off the 3 thin pieces of plastic behind the coupling itself so the bottle receives no drive at all.

Any i series a3 - the sub hopper auger bushings can become tight and prevent toner being added to the developing unit.

I have had expansion board failures causing the sub hopper drive motor(s) to turn constantly in the wrong direction. In the sub hoppers, one direction is for adding toner to the developing unti the other direction is for mixing refilling and level detection.

I have had rocks in the toners from heat damage cause destruction of hoppers and developing units - this is becoming more problematic.

in dirty machines - the level sensor PS can become contaminated resulting in the machine trying to add toner from an empty sub hopper because it constantly thinks its full - very common in the mining environment and filthy machines people have spilled toner into. the level actutor can be jammed in the full position causing the same result too.

[suomi]

Products: bizhub C250i;bizhub C300i;bizhub C360i

These trouble code C-2551 C-2553 C-2555 C-2557 can appears randomly. Sometime without action the TCR level recover by
itself a good level but sometime not

The agitating plate is gone out from its normal location, and has an impact on the detection plate position.




Replace agitating plate