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Hello,
I'm having an issue with a Xerox WC 7855(Firmware 72....)
1. Prints come out normal.
2. Scanning/Copying/Faxing on glass comes out fine.
However, when using documents on document handler (feeder), documents come out either almost blacked out or with rainbow colors. I've attached an example in this thread.
Any tips/suggestions are appreciated. Thank you.
are you a techOriginally Posted by wertyxhts
or end user? (suggest getting a service manual then)
I always start with power off..
disconnecting reconnecting all harnesses in the ADF to all interconnecting boards.
Tech.
Reboot fixes the issue for about a few minutes (2-5 minutes). But issue comes back with same symptoms.
Will be back at device tomorrow. I will reseat all connections and try f/w update.
Are those examples side 1 and side 2 of a duplex scan?
If so then on this model it's going to be faulty SBC or corrupt NVM. SBC is the only board the side 1 (via IIT PWB and Backplane PWB) and side 2 scan assembly (via Pyxis PWB) have in common.
Before changing any boards though head into diagnostics and initialize the scanner NVM. SBC replace as a last resort.
When duplex scanning, only first page has defect. Second side comes out okay.
Initialized scanner NVM. Also re-seated connections. Still same issue.
Would you happen to have the part number?
Last edited by wertyxhts; 05-15-2019 at 04:26 AM.
Ok if its only 1 side affected then its not the SBC. more likely the IIT PWB or Pyxis PWB depending on which side has the issue.
Write 1 and 2 on opposite sides of a sheet of paper and copy duplex through the dadf with the number 1 facing up.
If the number one side is bad but 2 okay its the IIT PWB. If the number 2 comes out bad but 1 ok its the Pyxis PWB.
Part numbers:
Pyxis PWB: 604K89991
IIT PWB: 960K61760
*EDIT*
I've read you first post again and noticed you say its fine from the glass. That rules out the IIT PWB and leads me to think its the Pyxis PWB which sits on the back of the SBC tray (3 thumb screws and slides out as a unit)
Thank you Richard, will look into this. I will update with results.
Let me know if you need a quote on any parts, we have a pretty vast parts dept with pulled used, tested working parts.
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**UPDATE**
Replaced the Pyxis PWB. Same result.
On DADF using duplex, side 1 has same issue, side 2 comes out okay still.
On glass, copies are shifted about 1/2 inch to the left and is a lot lighter than going on the DADF.
Thinking about replacing IIT PWB / SBC. Thoughts?
In Diagnostics try performing white reference setup, run the paper through three times each for DADF and scanner, i'd be interested to know the results of the 3rd pass.
It could be the side 2 scan assembly inside the DADF, not had a bad one yet on these machines but theres always the posibility.
After ruling out the Pyxis, the only other parts related to scanning are the IIT PWB, Backplane PWB and SBC.
Start with IIT PWB, remember to move the EEPROM chip from the old board to new one though unless you have a new chip.
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