konica C550 double imaging black only

[acsolutions]

Hello, double imaging black only! I checked the condition of the all imaging units, fuser and transfer belt, all looked good so I replaced the black I/U and still same problem! I went through all the calibrations in the image quality section in service mode. I made adjustments to the primary transfer and secondary transfer, I cranked the primary to 7 which almost totally cleared the problem,I cleaned the contacts on the back of the transfer unit and adjusted the contacts on the machine side and still the same problem. I'm thinking about the transfer unit or the HVT, any suggestions would be great! Thanks

[Synthohol]

have you stopped the image in the fuser and looked at the upper roller to see if toner is sticking to it?? maybe thats the culprit?
without looking at a pattern its hard to tell.
i usually roll the paper so the beginning of the double images are on top of each other and sometimes that gives me the diameter of the object making the transfer.
can you see the double image on the transfer belt?
set regular paper and set the tray to thick 2 and see if the issue remains, that will bump up fuser temp and voltage.

[acsolutions]

have you stopped the image in the fuser and looked at the upper roller to see if toner is sticking to it?? maybe thats the culprit?
without looking at a pattern its hard to tell.
i usually roll the paper so the beginning of the double images are on top of each other and sometimes that gives me the diameter of the object making the transfer.
can you see the double image on the transfer belt?
set regular paper and set the tray to thick 2 and see if the issue remains, that will bump up fuser temp and voltage.

Thanks. Those are good points. I'll be going back with a fixing unit and a transfer unit to tomorrow. I just don't know why it only does it on black and not color? 2016-04-28 16.12.03.jpg2016-04-28 16.13.29.jpgdoing single color and it's fine only black

[Synthohol]

have you cleaned off the PH window?

[acsolutions]

I was going to but there was no wand with the machine. Usually light areas when dirty, have you seen this issue with a dirty laser window? Did you look closely at the leading edge and the tale end of each line? It's hard to see even if you zoom in! Ghosting!

[minimerlin]

I am 100% sure that your problem is that the transfer roller guide plate (metal plate to the right side of the sponge roller when you open the door) is missing the mylar stick on mod to stop this actual fault!
Seen it many times in the past. Fixed on the later 552 series machines by changing the guide plate to plastic!

Part number is A00H703400. Guide Sheet!

Item number 45 on page 46 of the C550 parts manual Dec 2010 issue! Also shows where it is located. The fingers of the sheet must line up with the edge of the plate that it is stuck onto.

Let me know if I am wrong! lol

[Synthohol]

, have you seen this issue with a dirty laser window

Actually yes. Just yeaterday with a c552 magents spotty streak across middle of copy or print. Thought dv failure but when I took out the IU there was toner scattered all on the laser glass. Cleaned and stripe went away.
Actually I hope its what ^^he^ said. There was no wand in either tray or in the front door?
Sometimes its hidden in a compartment in the front of tray 1 or 2.
Good luck!