MX5001 back half of black images greatly faded

[copyguy1]

From what I am reading, you may want to look back at the laser shutters. Sharp did have trouble with them on the mx2600 series. These are basically the same machine. Also make sure to set sim 50-10 setting a to 100 then run 50-22.

[Akitu]

Not certain on seal. Will check later today. Earlier before this problem I had looked at the DV T.B. and had checked the machine for toner spill - not seeing any and also then since we changed developer hadn't been concerned re the seal. But at this point I will jump at any thing to check. Agency has been happy with our responsiveness and accepts that much of the issues are due to their gross negligence - so we have "some" time but very soon this is going to become a pressure point.

I just recently fixed a 5001 with this same problem using the seal, upon examination I wasn't seeing any spilled toner or DV, however the black dev unit was almost entirely empty within a matter of 2 months the first time I went to replace it after I first started troubleshooting it. They hadn't even done 5k. Wouldn't hurt to check, and as of yet I'm still not 100% certain my own 5001 is fixed, but unfortunately it's one of those fixes you throw in the machine and just wait and see. Haha

[Sam Tofu]

Will check into this more later today. Thanks for so much support.
BTW I have attached a scan of the clear plastic pawl like item. - you will have to look around on the 2 PDF pages
but they are there. The one with the black background shows the 2 shafts coming off of the pawl like piece.
I am really at a loss as to where this could go in the machine

Here is my description from 2 days ago on the post
One last "what is it" question...
BTW, I will try to scan a pic of this clear plastic picker finger or pawl- like mystery piece. Not certain where it came from.Customer said forgot to tell me about it. They found it somewhere inside right side door the day the fading issue started.
The piece looks like an oversized picker finger (in that it is much fatter and slightly larger)has two small flat shafts coming off the pawl, each with a hole at the end of both that appears to be for a small shaft to go through. It is NOT FROM FUSER. Doesn't look like pic of separator pawl for transfer belt than was shown in a T.B.

[Lawrence]

does this machine have the big saddle stitch finisher? I think that is the little flag you have to attach to the deleivery unit exit sensor. They are known to fall out. No big deal. It will be located between the machine and the RBX paper bridge unit.

[Sam Tofu]

Yes has a saddle stitch.That really helps!. thank you Lawrence Never looked over there - customer said they found it when they cleared jam by fuser. I should have asked and listened more deeply to what they really said

OK so I am going to re seat connectors on all of PCU , Hi voltage and the Primary Transfer.

Some trepidation in that the only board repair we know for Sharp is HyTech and they only have a 4001 series
Ambassador/Midwest only do limited Sharp repair and don't cover these items.

I have been leaning toward the PCU yet as black cat brought out - depending upon the particular aspect/phase of this issue - it seems a case could be made for any of these three boards.

ALSO does anyone know if black shutter is not opening will the Laser unit test still show OK. (WE did laser test the other day and it came up OK.)

[copyguy1]

That is the exit acctuator for delivery unit when installing paper pass unit for finisher. Also on machine problem if dv is missing it probably is in waste toner container. Which is caused by seal inside dv box (tb). or by a drum that is damaged on the end AND ARCING

[DavePo]

Will check into this more later today. Thanks for so much support.
BTW I have attached a scan of the clear plastic pawl like item. - you will have to look around on the 2 PDF pages
but they are there. The one with the black background shows the 2 shafts coming off of the pawl like piece.
I am really at a loss as to where this could go in the machine

Here is my description from 2 days ago on the post
One last "what is it" question...
BTW, I will try to scan a pic of this clear plastic picker finger or pawl- like mystery piece. Not certain where it came from.Customer said forgot to tell me about it. They found it somewhere inside right side door the day the fading issue started.
The piece looks like an oversized picker finger (in that it is much fatter and slightly larger)has two small flat shafts coming off the pawl, each with a hole at the end of both that appears to be for a small shaft to go through. It is NOT FROM FUSER. Doesn't look like pic of separator pawl for transfer belt than was shown in a T.B.

Looks like the end off the paper sensor in the Exit unit. It is the one put on when you add a the paper pass unit.

[Sam Tofu]

Thanks for help on where the piece goes. At least that is "fixed". OK here is where we are at.
Desperately, looking for any further clues.

Quick Summary and current status:
After replacing belt unit due to labels: Good copies for ~400 copies then called on ½ page faded issue.
Only on black. Color and Single colors OK.
Initially, as labels also on black drum; Drum, MC and Developer where replaced.
Developer calibrated at 128. Still fading issue and then swapped out entire process unit with Cyan. No difference.
“Sky” shot with “panic-stop” at this time was leaving drum coated evenly with no fading issue. Fading appeared on belt.
Sim 44-6 at this time gave us the K_HV_ERR. New Belt Unit found to be defective.
Warranty replacement belt unit sent to us. With new belt, still had faded issue but quickly after 1 copy then went to entire page faded and then blank copies with black.
Then “Sky” shot with “panic-stop” at this time was leaving drum not coated at all! No toner from Developer to Drum. Keep in mind swap out of Process Unit was also done. As well as a rebuild.
Ran Laser Test. Even taped the plastic flap that is closed in standby (one over Laser protective glass) open and tried a copy.
Checked and reseated board connectors.
Now the biggest ? as it shifts the issue in perhaps another direction is issue of 1^st was OK on drum now not even on drum.
Is the Main Process PWB the only thing in common here?
Also connections, grounds in back where belt, DV and Process unit mate with machine were all checked for looseness and obstructions etc.

FYI: Production date May 2010. Meter from my "memory -slightly under 95K on black and just at 72K on color. We did see T.B re toner spills on DV unit. No sign of issue, errors not in logs. Also Devel was then replaced. So not thinking that is immediate issue for us. However, we will address this as well as firmware updates etc. once we can get machine back to basics.

[bilyahn]

One thing since you just mentioned that you haven't updated the ROM. There is a new one from March2011 and a tentative one from May. Everytime that I've been to the Sharp schools in the last few years they "harp" on updating the ROMs as the first step in any troubleshooting process. Don't think it's relevant in this case but it appears from your statement that it hasn't been done. Current ICU Main 4.07.J2. I have a few of these units out there so am keenly interested in the solution!!

Good luck.

Bil

[Sam Tofu]

Sent in MC _PWB and Primary PWB for testing and possible repair.
MC board black circuit had several issues. Repaired.
Re-Installed boards ALL WORKING OK

So the three issues we had
1. Labels stuck all over the place - cleaned up replaced drum,blade, MC kit and developer
2. New transfer belt unit to replace one damaged by user fingernails getting labels off.(but was defective- partially cause of light copies on middle to rear of copy)
Warranty replacement fixed that.
3. Black Copies then all faded. MC -PWB repair fixed that.

Customer Happy. We are happy cause fixed before Thanksgiving.

THANKS AGAIN for everyone's attentive help on this.

HAPPY THANKSGIVING TO ALL