I am having a tricky problem on a KM 8030. The transfer belt is getting coated with toner. This happens at random and all of a sudden: On friday I swapped the transfer belt assembly, the drum cleaning assembly, and the main charge assembly. I came back this morning and the belt was clean. I proceeded to make 20 copies to test the machine, opened the fuser drawer, and the problem re-appeared. Over the weekend, the user ran approx. 600 pages through with no problem. After the belt becomes coated, the resulting copies out are mostly clean and clear; only a slight background on the back of the pages Any suggestions

(from the belt).

This might just lead to more questions ...

... but to me, this looks like the transfer current is staying On between pages, maybe On all the time. So it's pulling the waste toner right off the drum and transfering to the belt (since there's no paper, and no physical belt cleaning mechanism). The four blank strips are probably there to minimize toner buildup on the drum separation claws.

Does this point to the HVT, or engine PWB? I don't know. I think that I would figure out the signal voltage that enables transfer current, then monitor that signal (maybe YC6-11 @ engine PWB-TRF REM to ground). If the signal is staying On, I'd replace the engine PWB first. If the signal is not staying On (but still getting transfer current) I'd replace the THV PWB (under the transfer belt).

If you disagree with my reasoning, I would like to hear why. =^..^=

Had one doing something similar, it was the THV assy under the xfer belt.

I have the Transfer HV assembly on order from Kyocera. Will let you all know how it works out.

UPDATE - It has been a week since I put the new HV transfer board in that sits beneath the transfer belt and have had no complaints from the customer. So I guess that did the trick... Thanks all for your help.