yellow halftone screens

[Milo Wilson]

See if you guys might have an answer for this issue on an iGen 4.
Have a machine that is printing blotchy patterns of yellow through an image that should be gray.
I'm trying to upload a sample but having some problems.
I have cleaned/swapped with magenta ; donor rolls, wire mods, charge screens and wires, all color boards in card cage. I have cleaned the scan lamp. The yellow will not pass CMT because of this also.
It is not random but I can't see when I use dc 923 for yellow developer.

 

[Milo Wilson]

Found magenta toner on the yellow laser. Should have checked that first...LOL

 

[peels]

on the glass?

you know, I cleaned that a hundred times as part of regular troubleshooting of streaks, never finding anything! so then I didn't do it for awhile.

first few times I didnt......voila! big purply blob on the magenta lens! ugh easiest things sometimes.

 

[Milo Wilson]

Yes it was on the laser output lens. Happened during shipping. Everything is up and running now though

 

[gavywill]

Where are these screens located? i may know what it is already just no good with names lol

 

[Milo Wilson]

I meant when printing lighter shades of yellow (50 % and lower) the image would be a blotchy pattern and it turned out to be magenta toner had fallen down and gotten on the yellow laser window output.