C258 white spots from cyan only

[Scarekrow]

Hello chaps,

I have a c258 just come in, only done 19k colour but the cyan is leaving little mouse size poo white spots all over a sky shotted page.

so swapped the drum, no change, took out the dev unit which looked fine, full coverage, spins ok, toner levels are normal, nice and clean, all other colours ok so can't be the belt.

so to test I swapped the magenta dev unit with the cyan and test printed and the fault followed the cyan, therefore it has something to do with the dev unit, but, what is it?

I have tried to upload a jpeg but the site just keeps giving me error why is that?

[avecosat]

better if you send a test, thanks

[copyman]

Hello chaps,

I have a c258 just come in, only done 19k colour but the cyan is leaving little mouse size poo white spots all over a sky shotted page.

so swapped the drum, no change, took out the dev unit which looked fine, full coverage, spins ok, toner levels are normal, nice and clean, all other colours ok so can't be the belt.

so to test I swapped the magenta dev unit with the cyan and test printed and the fault followed the cyan, therefore it has something to do with the dev unit, but, what is it?

I have tried to upload a jpeg but the site just keeps giving me error why is that?

If off lease machine don't discount the prior service company swapping out the dev unit with bad unit! Sorry to say it happens all the time when the machines are sitting in dealers warehouse waiting to go back to leasing company / wholesalers

The cyan dev unit is very common to lose developer due to over life drum. Even though it looks good on mag roller it's still low on developer. Some times you can get lucky and go into service mode and add cyan toner (which has developer mixed in) and bring dev level in state confirm back to 6 - 6.5%. If not can add some aftermarket developer (copylite products). both optins way less than $500+ for new developer unit. Oh yea, still needs new drum or it will happen again. Konica minolta says this can happen from "any" consumable being overlife but I've found it's usually the drum of that color dev that caused it.

[tsbservice]

Hello chaps,

I have a c258 just come in, only done 19k colour but the cyan is leaving little mouse size poo white spots all over a sky shotted page.

so swapped the drum, no change, took out the dev unit which looked fine, full coverage, spins ok, toner levels are normal, nice and clean, all other colours ok so can't be the belt.

so to test I swapped the magenta dev unit with the cyan and test printed and the fault followed the cyan, therefore it has something to do with the dev unit, but, what is it?

I have tried to upload a jpeg but the site just keeps giving me error why is that?

Attach MML list to see voltages cyan may be off.

[goose]

Generally dev units depleted of developer give a banding or pattern, quite often a diagonal or diamond effect.

I have seen devs behave like this with the white spots when the machine has come in from a trader where it has been kept in a cold or damp environment and damp has gotten into the unit. Generally they clear up after a couple of days of normal temperature.

[B0265]

IF this does not clear up after a couple of days of normal temperature like goose wrote, try this:
Set "2nd Transfer Adj" to a lower value.

[Scarekrow]

better if you send a test, thanks

https://www.copytechnet.com/forums/attachment.php?attachmentid=53290&d=1652439902&thumb=1&stc=15329053290

[Scarekrow]

better if you send a test, thanks


Ok

[B0265]

Judging from this sample I would rather increase 2nd Transfer voltage.

[avecosat]

if it's only in cyan I think it's the DV

[Scarekrow]

Judging from this sample I would rather increase 2nd Transfer voltage.

Ok Ill have a look at that, that will effect all units thought won't it? even though the other are ok.

[Scarekrow]

Ok Ill have a look at that, that will effect all units thought won't it? even though the other are ok.

Also if the print is like it is while on 1st tranfer belt then there's no point fiddleing with the 2nd TR

[copyman]

Also if the print is like it is while on 1st tranfer belt then there's no point fiddleing with the 2nd TR

I wouldn't adjust any voltages, etc. I have many of the 4 & 8 series that I've never had to make any adjustments for quality issues. Just go into service mode and add cyan toner until you see the levels go up. This is the first thing I would try and doesn't cost anything but 10 mins of your time!

By the way not sure if anyone asked, are you using genuine toner?

[B0265]

Ok Ill have a look at that, that will effect all units thought won't it? even though the other are ok.
On your intial description I thought that the white spots were much smaller, that problem normally is more visible on cyan.
When I saw the picture you posted it don't look like this problem but you can try playing with the 2nd transfer to see if it have any effect anyway.

[Scarekrow]

So today I tested and it seemed to be better, I manually added toner and tested again and those white missing bit have now gone all together so it must have been just a bit of damp effecting the cyan.

Thanks for all your helpful advise.

[tsbservice]

I wouldn't adjust any voltages, etc. I have many of the 4 & 8 series that I've never had to make any adjustments for quality issues. Just go into service mode and add cyan toner until you see the levels go up. This is the first thing I would try and doesn't cost anything but 10 mins of your time!

By the way not sure if anyone asked, are you using genuine toner?

He-he wise man :)

[copyman]

So today I tested and it seemed to be better, I manually added toner and tested again and those white missing bit have now gone all together so it must have been just a bit of damp effecting the cyan.

Thanks for all your helpful advise.

No it wasn't a bit of damp it was a bit of low on developer. As I tried to tell you in my first post. I gave you the ammunition but you just didn't want to fire the gun :)

Anyway glad you got it going.

[Scarekrow]

No it wasn't a bit of damp it was a bit of low on developer. As I tried to tell you in my first post. I gave you the ammunition but you just didn't want to fire the gun :)

Anyway glad you got it going.

Yes, you're right, I didn't think it through, with the levels being ok, the mag roller looking fine and the low colour print count, I overlooked what you said or it didn't seem to make sense. Walking away for a day and returning with a clear mind helps.