I went out on a 1515 the day before yesterday, the copies were very overtoned and the back side was dirty too, with a black line about 1/2" wide at the top of the page (back side)
I removed the toner bottle and tried to detone it but it kept getting jammed in the fuser due to the black line at the lead edge.
Went back yesterday, replaced the fuser rolls and the PCU. CQ came back immediatly. Ran some more test copies and left.
That afternoon they called back. When I got there the symptoms were exactly the same.
The ID sensor was reading 3.8Vsg and 4.8 for Vsp. Vts at 2.60. As I tried to detone it (make a copy, clear the jam) the VTs gradulaay went down to 2.88. So I open the right cover and triped the switch. I expected to see a few revs of clean drum then the patch then clean again.
What I saw was an end to end coated drum until the 3 beeps then a clean drum for a couple of revs. No patch.
So now I know where the back side dirt was coming from.
I cleared the memory and the ID sensor and TD sensor changed but still out of range.
Heres how I see it: the PCU is getting overtoned because the ID sensor is at 4.8 (undertoned)
The ID sensor and TD sensor are OK becasue they are giving readings that change. The ID sensor must be taking the patch reading at the clean drum time. But if thats so, why is it higher than Vsg (3.8)
I'm hoping that someone has seen this and can shed some light on it.
I have ordered a HV supply and a BICU.
14K on the machine and firware is at "C"
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