I replace it my self but you need a extra hand because its a big job and you cant do it alone and you need someone to hold the upper part assembly. The reason you having that problem because the cover of the LED unit is not opening when you bring down the door/closing the top cover. check the mechanical assembly on the LED unit covers and gears.
I am having the same problem but my gear is in place. There does seem to be a small gap in the gear. I get full edge to edge color coverage and my transfer unit has a swath of color acroos the entire width..
We found the problem!!! It's on the LED Assembly and it's a gear no. 28, part no. 807E17570. The gear was completely broken and not even noticeable. The function of these gears will rotate the shaft and will open the LED cover. But as you can see on the photo it looks like electrical problem, component problem or high voltage problem.. I attached the actual few photo's of it. Good luck guys!!
If you are unable to get the machine to turn on properly and have done all those things that you mentioned the only thing I can suggest is that you have a Xerox technician look at the machine or if it is still under warranty possibly having the machine replaced. You are past my area of knowledge on this one as I am not a technician. If you are in the US you can call 1-800-821-2797 to request service.
@CherylO-Xerox these solution you mention can be apply when the printer is working properly. The photo shown here was the first test page when you fist turn on the printer and so no mater what you try to do with it or to print you will have the same result, we've done hard reset from the IP board and NvRam as well. We tried replacing IP Board, High voltage board, Engine board, imagine unit, transfer belt and fuser. We did called already the tech support from XEROX and done one 'n one troubleshooting but nothing resolve the problem, we also check(buzz) all the cables and connectors but still no luck. For every time you turn on the printer the toner drop'n to the transfer belt and going to the waste and so I did may only 10 test page and from the 100% new toner only magenta went all the waste and now it is empty. Magenta and black always bleeding or flooding the transfer belt and when it was finished or empty it will drop the cyan and the yellow. We also checked the ADC assembly and ADC auto test and the result same story... If you need the case reference from Xerox I have it.
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