[Misc] KM 2550 BLANK COPIES

[kyogenius]

Sorry guys hv been away a while but still have my machine with the problem of blank copies, i have tried nearly everything on it on another working machine,they all fine, i mean dev unit ,drum unit,laser unit,all boards except power source pcb, all things seems working, could it be my power board, any suggestions, the best i got is a very faint image on one edge if i set all my settings on darkest.

Could it be my dev bias, hw can i check it ,if its likely

[JR2ALTA]

Re: KM 2550 BLANK COPIES

Did you replace the High Voltage board?

[kyogenius]

Re: KM 2550 BLANK COPIES

SURE i even tried it on another machine, its fine

[JR2ALTA]

Re: KM 2550 BLANK COPIES

Go ahead with the Power Supply board. Sorry, I have to ask....it's blank on internal prints too, right? Cuz these machines have an issue with mirrors clouding up.

[blackcat4866]

Re: KM 2550 BLANK COPIES

Is there any latent developed image? I'm guessing no. =^..^=

[JR2ALTA]

Very faint on the edges

[blackcat4866]

Re: KM 2550 BLANK COPIES

So there may be a transfer or separation charge loss, but you won't know for sure until the first problem is resolved. You could have developing drive issues, but I think that's unlikely, it would affect image quality evenly in the main scan direction. Your primary charge is intact or you'd have black prints. Drum ground fault would also affect the image quality evenly in the main scan direction.

That leaves developing bias voltage, or possibly a generic toner or wrong toner issue.

Personally, I'm leaning towards wrong toner. Any remnants of OEM toner would remain at the far ends of the developing unit.

Change the toner and vacuum out the developing unit. Then run U130 to refill the developing unit. Otherwise it could take several hundred pages to deplete the generic/wrong toner. =^..^=

[aodtech]

Re: KM 2550 BLANK COPIES

Check the metal contacts that go from the High Voltage Board to the Transfer/Separation and Drum/Developer. They are think metal strips which are mounted to a plastic housing. I've had a flange that seats the metal strip break and there wasn't proper connection between the contact and the transfer roller.


Contacts.pdf

[kyogenius]

Re: KM 2550 BLANK COPIES

thanks guys ,i hv tried nearly everything on this machine but still NO breakthrough, my only conclusion could be a broken cable or something related to wiring,however am still willing to try anything . i got a working machine beside this faulty one. what else can i try,

any suggestion is most welcome no matter how stupid it may sound

[blackcat4866]

Re: KM 2550 BLANK COPIES

Do internal prints come out OK? From what you've said, all that's left is wire harness and charge contacts. That's all I've got. =^..^=

[rashid120]

Re: KM 2550 BLANK COPIES

Sorry guys hv been away a while but still have my machine with the problem of blank copies, i have tried nearly everything on it on another working machine,they all fine, i mean dev unit ,drum unit,laser unit,all boards except power source pcb, all things seems working, could it be my power board, any suggestions, the best i got is a very faint image on one edge if i set all my settings on darkest. Could it be my dev bias, hw can i check it ,if its likely

friend i will give you solution for your problem....but it will take time for you to open some parts that you never open before....i faced same problem and exactly in this model KM-2550. (replace the housing for main changer)(remember this housing not included in the main charger assembly ..actually it is a frame where main charger fits inside the machine.....it may leak or damaged)..please try and update.Thanks and regardsRashid Iqbal