Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

[srvctec]

Had a call yesterday from a guy I've known for decades and he's very good about describing issues so I knew it was exactly as he said. "Black vertical lines ONLY on color prints. B/W prints are perfect." So I grabbed a belt and the color drums and off I went. Here are the test prints he showed me upon my arrival.

ALL PHOTOS IN THIS POST ARE WITH THE LEAD EDGE ON THE RIGHT not on the left as depicted on the pages since they came out face down. Had a brain fart!







Color registration is WAY off as well. Also, notice that the black lines (they are actually black and not process black when looked at under magnification) go out past erase. WTF!!? <(My main reason for this post!)

Here are my test pages upon arrival. The first thing I noticed was the polygon mirror was dirty because of the light image at top of page (rear of machine).




This one is after I pulled the power plug and let the machine set for 10 minutes while I cleaned it, thinking maybe it was a memory issue or some sort of glitch. Color reg way off in it as well.


B/W test page is perfect.


The following were all at halftone set at 100.










Sooo, why in the heck are there black lines ONLY on color prints, going out past the erase!!?

The only thing I can come up with is the laser was bouncing off dirt inside the P/H unit but then why aren't there lines on the black prints and test page? And I only cleaned the polygon mirrors and first lens, nothing else inside of the P/H. I guess I did blow off the SOS sensor but that would still cause issues with black if it was dirty.

[srvctec]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

After cleaning the polygon motor mirrors and also the back side (laser side) of the collimating lens (I think that's what it's called; the first lens the laser passes through after hitting the polygon mirrors). Disregard the "missing" image at the top of the page because it's glare from the overhead light. In person, it's absolutely perfect.



And a photo of the deconstructed machine.

[Woxner]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

cl the idc sensors and run reset reinialize in stablizer then gradation then stableizer. i see your colors are out of alignment. this fixed it for me. how much on drum units? start simple.

[srvctec]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

cl the idc sensors and run reset reinialize in stablizer then gradation then stableizer. i see your colors are out of alignment. this fixed it for me. how much on drum units? start simple.

Ummm, all you have to do is read the title and the reason for me including "FIXED" in the title is so I wouldn't get suggestions on how to fix it.

It's fixed but why are the black lines extending out past the erase?

[blackcat4866]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

I'm going to speculate that the contaminant was throwing off the balance of the black polygon mirror motor. The vibration was causing compressions in the black image, which would show up in the voids. And since color calibration is based on the black image, the colors were trying to calibrate to a moving target.

That's my guess. =^..^=

[mascan42]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

I hate to say it, but once you opened the print head up and exposed it to the elements, doesn't that pretty much guarantee this will happen again at some point?

[tsbservice]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

I hate to say it, but once you opened the print head up and exposed it to the elements, doesn't that pretty much guarantee this will happen again at some point?

Not necessarily.

[Toxic]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Had this problem many times on 4 and 8 series.
Main symptom of much dirty poligon mirror is faded print on the rear side machine.
Mascan42 is right, it will come back but not very soon, it depends much if machine is in dirty environment.
Typicaly i see this on machines with 200k or more counter and after about 2 years or more.
This type of laser unit dont have good insulation from outside obviously and fine dust can get inside.

[REGSIS]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Had this problem many times on 4 and 8 series.
Main symptom of much dirty poligon mirror is faded print on the rear side machine.

Faded print yes, but vertical lines NO.
Could be PH unit control board.

Had these sypmtoms on 308e.
They were very strange. Every day until noon machine produced black vertical lines. Image was zoomed in sub direction. In the afternoon prints were OK.
After 10 day there were only bad prints all day long.

That was KM machine under lease, so they replaced it with a new one.

My guess was PH unit control board but never had a chance to try that solution.

[Oystercopy]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Interesting that you guys have had issues with dirty lasers?? I've never had one out in the 8 series, even in dirty environments... huh?
OC

[Oystercopy]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Interesting that you guys have had issues with dirty lasers?? I've never had one out in the 8 series, even in dirty environments... huh?
OC

[srvctec]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Faded print yes, but vertical lines NO.
Could be PH unit control board.

Had these sypmtoms on 308e.
They were very strange. Every day until noon machine produced black vertical lines. Image was zoomed in sub direction. In the afternoon prints were OK.
After 10 day there were only bad prints all day long.

That was KM machine under lease, so they replaced it with a new one.

My guess was PH unit control board but never had a chance to try that solution.

Once this machine started doing it (only on color), it never stopped the black lines until I removed the P/H and cleaned the polygon mirrors, so I'm hoping that was the issue and not P/H board. Time will tell.

[REGSIS]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

To remove the PH unit, you must first remove power supply board and small board on the bottom with two flat cables. That's a PH unit control board.

So, you probably "solve" the problem by dissconnecting and connectin flat cables into it.

No dirt can cause the vertical lines. Dirt in PH unit can only cause faint images. This is an electrical issue.
This PH control board is cheap, better hope it is the cause rather than MFP board.

[tsbservice]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

I have had those lines twice. First time machine was close to 2 million counter so we swapped machine. Second one I did swap board prior whole PH unit that didn't work. At the end I leave original machine's board and swap PH unit with another used(but good) one PH unit that fixed it.

[blackcat4866]

Re: Black lines ONLY on Color prints C368. FIXED but still curious about symptoms.

Our dealership is primarily Toshiba, but also Kyocera, Konica Minolta, Lexmark, Kip, HP, Canon iPF, and others. The majority of dirty lasers I've seen are Toshiba & HP, but only because they made up the largest proportion of the machines. It's more about the environment than about the make.

image.jpgimage.jpg

=^..^=