C300I problem background

[Massimiliano]

good morning,
I have a c300i with 110,000 copies all drums at 50%.
when the customer prints in color the pages come out with a recycled paper type background, in black instead everything is ok. (I attach a photo)

can anyone give me a solution?
Thanks

[Synthohol]

wheres the photo?

[Massimiliano]

sorry I forgot to attach.

here they are, I also attach the print management list

Thanks
IMG_2595.jpg

C300i.pdf

[copyman]

I would look at black drum, even though only 50% drums can still fail, especially on low volume accounts. Are you using aftermarket toner?

[Massimiliano]

original toner...
in mono prints the defect does not appear
Thanks

[Gift]

Looke a bit like a worn/aged drum (did you inspect the drum surface? I've seen many showing bare metal at both ends of the drum cylinder) or somebody messed with voltage-related settings. If the drum looks ok and you like to "fiddle" you can try initializing image stabilisation data and print the test page again without doing a calibration.

[Massimiliano]

Good morning,
I was at a customer's, I replaced all the idrums but it didn't solve it.
then I also replaced the HV card, but the problem is not solved.

Help me please....

[occus]

Do you replaced drums with new original drums(new chip)? i had this on a several c250i's.
Easyway is to set adjustments in background voltages it will be better but not perfect.

[Massimiliano]

Do you replaced drums with new original drums(new chip)? i had this on a several c250i's.
Easyway is to set adjustments in background voltages it will be better but not perfect.

hello, new original drums

how do set adjustments in background?
thanks

[Cantechman]

sorry I forgot to attach.

here they are, I also attach the print management list

Thanks
IMG_2595.jpg

[ATTACH]n1616944[/ATTACH]

I had that exact issue before, tried every adjustment. Replaced the HV connectors, transfer belt, transfer roller, black drum, nothing worked until I replaced all 4 drums with new ones, it's been fine since.

[Synthohol]

only because you didnt mention it, have you tried a background data reset and stabilize? then all the gradations.
i would have tried that before replacing anything.

[Massimiliano]

only because you didnt mention it, have you tried a background data reset and stabilize? then all the gradations.
i would have tried that before replacing anything.

yes I had already tried these things

[and]

Vpp-C1 Vpp-M1 Vpp-Y1 Vpp-K1 after you replace the drum?
You have all LD Light value at 1400... strange.

[Massimiliano]

Vpp-C1 Vpp-M1 Vpp-Y1 Vpp-K1 after you replace the drum?
You have all LD Light value at 1400... strange.

yes even changing drum, values remained at 14oo, even after replacing HV Board.

Very strange for me too

[occus]

hello, new original drums

how do set adjustments in background?
thanks

Bild_2025-05-21_153046128.png
You need a magnifying glass to check the colors of the dots.
Try not more then -3. But this is the dirty solution/workaround!

New drums was the solution in my cases, or sometime one of the DV.