[Misc] MX-M550

[vlad_robas]

Hello,

In march we bought this machine from a second-hand dealer. Machine had 28K copies on it back then and a fine grey background slightly visible. We then replace the developer on it and we thought that was it but the background was still there so went to sim 8 and changed the byas if i remember correctly. We sold the unit three weks ago at 33K. Yesterday we got a call from custormer who sayid that he had made 12K copies on it and now machine has a background.
This is the only machine of this type that we ever had so we don't know much about it and worst we cant switch part's to localize the problem.
The machine realy look's that it has the counter that is showing.
I'm looking foward to find your opinions on this matter.
Thank you.

[JustManuals]

Re: MX-M550

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[bilyahn]

Re: MX-M550

Do a white reference calibration but the most likely cause is the scanner pwb. Unplug it and reseat all of the connectors and the problem will go away for awhile. Eventually you will need to replace it.

Good luck.

Bil

[blackcat4866]

Re: MX-M550

Does it have this background on just copies, or every print/copy. On this model there are exposure adjustments for each specific mode setting, i.e.: photo, text, text/photo, etc, etc.

On the preceding models: the AR-M550N there was a little problem. Sharp decided to increase the amount of toner in the toner cartridge, yet did not increase to volume of the waste toner container in that same cartridge. You can imagine what happened. Of a sudden, the waste toner systems started backing up when new style cartridges were installed. Sharp's idea of a solution was a complicated sequence of image quality adjustments designed to reduce the amount of toner on the paper, thusly reducing the amount of toner in the waste toner bin. A little side affect of these adjustments was significantly lightening the image quality. Imagine that! Less toner means lighter copies! Who would have thought?

As a result of the poor quality images resulting, nobody actually did the adjustments exactly like Sharp wanted them done. Everyone had some little thing that they did differently to improve the standard image quality. I'll see if I can find the bulletin describing the image quality adjustments.

I was not working on Sharp products when the MX-M550N came out, but I'd imagine that the same procedure would apply.
Can you confirm that Bil? =^..^=

[bilyahn]

Re: MX-M550

Does it have this background on just copies, or every print/copy. On this model there are exposure adjustments for each specific mode setting, i.e.: photo, text, text/photo, etc, etc.

On the preceding models: the AR-M550N there was a little problem. Sharp decided to increase the amount of toner in the toner cartridge, yet did not increase to volume of the waste toner container in that same cartridge. You can imagine what happened. Of a sudden, the waste toner systems started backing up when new style cartridges were installed. Sharp's idea of a solution was a complicated sequence of image quality adjustments designed to reduce the amount of toner on the paper, thusly reducing the amount of toner in the waste toner bin. A little side affect of these adjustments was significantly lightening the image quality. Imagine that! Less toner means lighter copies! Who would have thought?

As a result of the poor quality images resulting, nobody actually did the adjustments exactly like Sharp wanted them done. Everyone had some little thing that they did differently to improve the standard image quality. I'll see if I can find the bulletin describing the image quality adjustments.

I was not working on Sharp products when the MX-M550N came out, but I'd imagine that the same procedure would apply.
Can you confirm that Bil? =^..^=

I'll have to look up the bulletin as well. We never did it, well maybe one time, as the gain didn't warrant the PITA and reduced image quality. If toner has backed up in the waste auger you will also get the same result. Good catch!! But you would normally get noise associated with that problem plus F2-37 and eventually F2-31 codes.. Easy check for this is to pull out the toner and look to see if the waste toner is full.

Bil

[blackcat4866]

Re: MX-M550

Your memory is better than mine. There was F2-31 codes, resulting from toner spewing on the drum mark and PCLED sensors. And toner on the backsides of copies. And the clicking of the cleaning unit gears being chewed up (brush drive gear 21T: NGERH1549FCZZ, and brush drive gear 30T: NGERH1549FCZZ).

Does your fuser have a web installed? AR-M550N's had a modification to add a web to cleanup toner specks collecting in the fuser. I think this problem alone probably killed sales of this machine. Every single visit we had to brush out the toner & paper dust collecting in the fuser. And it appeared as a million little specks on the copies. =^..^=

[bilyahn]

Re: MX-M550

Easy for me as we still have quite a few of the ARM550 series and MXM550 series out there, so I am constantly dealing with the toner specks and waste toner problems. I don't really see the MXM623 series being any different but so far we haven't seen this issue with the newest series.

Bil

[vlad_robas]

Re: MX-M550

I went today and started the machine and was ok so i stayed till it printed about 2000 pages and it was ok. Now afther few hours he call me to tell that the problem is back in the meanwhile he sayid it printed 15000 (7500 sheet's). In the attachment's u can see the dot's but there are more grey dot's that can't be seen on this scan.
Waste toner was surprisingly empty or there was a lot of empty space in it.

[blackcat4866]

Re: MX-M550

To me, it looks like the specks from the fuser. The specks are too big to be just overtoning, or an exposure adjustment.
Bil, your opinion? =^..^=

[divad2k1]

Re: MX-M550

Dirty or broken toner receiving seal in drum unit could give this problem .

Do a hard stop and check if the dots appears on your copy before the fuser or not.

[vlad_robas]

Re: MX-M550

Dirty or broken toner receiving seal in drum unit could give this problem .

Do a hard stop and check if the dots appears on your copy before the fuser or not.

Sure isn't the fuser. If it was that seal why the problem would dissapear afther shut down?
The copier is working OK at an amount between 5 - 10 K of prints then it gives this problem. Afther an half an hour the cycle can be repeted.

[bilyahn]

Re: MX-M550

Had this happen in image send one time (MXM620N) but it was consistently there not random like this. I believe it is showing the imperfections of the original. You can actually look at the original and see where there are slightly darker spots in the paper and they will probably match up with the specks on the copy. Are the specks in the same spot on each page on all of the copies or do they move around? To test I would take the exposure out of auto and just default it to text to see if this happens, you may also want to adjust your 46-2 settings. Two questions; 1. Are you on a dedicated 20 amp line? 2. Is this only happening on copies or is it also on prints? If it is also on prints then it is not the scanner PWB but could be either the drum unit or fuser as mentioned above. What year was it made?

Good luck.

Bil

[vlad_robas]

Re: MX-M550

Machine is only used for print. And now user is only doing maximum 2500 pages/job and he is allowing machine to ''cool'' shutting it down for a while.

The problem was originaly happening often when we recived the machine on short jobs so we changed dev afther that he dindt do it anymore on jobs like 100 pages. So we sold it. So i dont think is about voltage line.
If i remember right is 2008.

[bilyahn]

Re: MX-M550

Machine is only used for print. And now user is only doing maximum 2500 pages/job and he is allowing machine to ''cool'' shutting it down for a while.

The problem was originaly happening often when we recived the machine on short jobs so we changed dev afther that he dindt do it anymore on jobs like 100 pages. So we sold it. So i dont think is about voltage line.
If i remember right is 2008.

Since it is being allowed to cool between jobs I would think that it points to the fuser being the most likely problem. Possibly a fuser web cleaning problem?

Good luck.

Bil

[vlad_robas]

Re: MX-M550

As i sayid earlyer i don't have experience with this model but i heard something about AR-M550 fuser problem's.
What exactly should i look for? Is not in my close areea so when i go there i have to be aware what to expect.