Printing issues: help to avoid 60+ kg of e-waste

trying to make it short, ask if more details needed.

Had the following issue (missing magenta, sheet is A3 fed of course on short edge):


What I've done with no different outcome:
- tried to replace the drum
- clean LPH with the wand
- calibrations
- replaced belt and IBT unit
- replaced fuser

then, shame on me, I followed with:
- remove all LPHs and developer units
- clean all LPHs and developer units
- put them all back in

since that, the printer only prints white or a very faint black. It seems to me that the toner is not sticking to the cleaned developer roll, hence no toner transferring to drums, hence no toner on the belt and no toner on the paper.

I know when a new (clean) developer unit is paced, usually it has to be filled, but I found nothing in regard in the menus in both normal or service mode. Service manual mentions ADC calibration which I tried but doesn't seem to be related (and should not be required as developer unit have not been replaced, just cleaned). Since that I'm sometimes receiving ADC-related warnings (ADC patch fail 092-67x).

I paid the printer (2nd hand) 250€ back in feb 2023 when it had less than 20K pages (and I printed about 1K since). Any chance I can fix it or is only option (considering how "much" I paid for it) to bin it?

Thank you very muc!

 

First check again if you pu it right the black developer assy and drum. Drum must have electrical link to machine ground otherwise you get faint prints/copies.

Print A3 paper with basic colours 50% yellow, magenta, cyan and black to see in what colour the lines appear.
If you print composite colour you dont know where defect is localized.
Then do same thing in the colour with defect and stop the machine while printing. Check if you have lines on drum or the lines appear on IBT. If they are on IBT look at the 2nd BTR for marks.
If they are ob cylinder then check LPH or uneven toner on developer assy.
You can swap LPH from one colour to another.

 

Thank you for your answer but I fear you missed the "since that, the printer only prints white (nothing) or a very faint black" and referring to the previous issue (documented in the attached image).

 

Check again where you disassembled.
You must have forgotten to put a connector in its place

 

that's (to be wrong/have forgotten something) what I wished for but doesn't seem to be the case: the only cables I disconnected are the 4x with 3 pins/cables (black, red white) going from each developer unit to the ATC Sensor PWB (and left the bigger connector with blue wires connected). If I start in service mode (service diagnostics 5.19.1) and then go ADC Output check, I get:
ADC Patch Fail: YMC
ADC Mini Setup Fail: YMCK

Which seems to me to tell something is quite wrong...

PS: As a B-plan: I found an extremely cheap WorkCentre 7835 with little page count (less than 10.000) but without toners. How can I check whether it is setup on metered or sold?

 

Could it be instead something mechanical? Ex. Developer housing/sensor or pipe considering I removed/cleanded/reinstalled everything (without opening the developer housing)? Thx again.

 

quick update: I filled up the black and magenta developers with some toner and I'm getting some output. I guess I shouldn't have emptied them (service manual says nothing on how to deal with developer units beside removing them ).

Hoping to get some further help but will keep posting updates in case this can help anyone else.

And I jsut realize I didn't mention something on the title (which I can't change anymore): this is about a Phaser 7500

 

after some research it looks like that after cleaning (emptying) the developers, they have to be refilled with their own material:

• 675K67550 Yellow
• 675K67520 Black
• 675K67530 Cyan
• 675K67430 Magenta

can anyone confirm? Thx!

 

For the moment your best friend is chapter 2 from service manual.
Read it all twice. Then search for word 'developer' in service manual and you'll find the procedure to change it and the part numbers. If you don't have the patience to do this, call a service tech before you damage the printer.

 

I have 3rd printing, sep 2010
Do you know if there's a more recent one?

 

Just to prove I am (and have been) doing my homework

Found another version which still says sep 2010 both has a blue arial "updated 4/6/15" statement on 1st page, I'll consider this is the most recent.
I had already been through it (I'm the first, in topics I know, to tell people to do their own homework and I try do so myself ) but, whether because I'm not an native english speaker or I'm not a print technician:

• I didn't understand that what Xerox calls "Developing Beads (toner+carrier)" at page 2-9 is the powder/material that fills up the developer. Then, one paragraph after, the naming seems to change to "thin semi-conductive sleeve".
• An image at the bottom of page 2-11 showing the extremity of the developer unit shows toner supply getting into the dev.unit. from top and developing beads outlet (toner carrier) getting out on the bottom. Again probably my comprehension but if the toner+carrier gets out of the developer, shouldn't that be replaced to keep the developer unit working?
• Page 8-50 (Replacing Developer Housing Assembly) has a caution note: "When removing the Developer Housing Assembly, be careful not to contaminate the Developer Housing Assembly." but doesn't give a definition on what contamination is and how to avoid it.
• Page 8-51 mentions "If this is a new Developer Housing Assy, install Developer beads (see REP 5.8)". Out of proper knowledge, I ignored this part because I wasn't installing a new developer. After your insights now I read this "if you install a Developer Housing assy that has no beads, whether because it's new or it has been cleaned, install developer beads"
• The instructions at page 8-56 now make sense. Q: "While keeping the Developer Housing Assembly level, carefully pour the entire contents of the developer mix package as evenly as possible over the two augers."; ok but... at level=at which level?

As per what I referred to as material/powder : the service manual only mentions the part numbers for both the developer and the beads (page 9-29), so my previous question still stays.

Considering the unit has less than 20K pages, I think it's worth spending 150€ to fix the issue I created but I'm having difficulties finding original Xerox material to do so. Here's what I've found:

• https://x4y.eu/en/workcentre/workcentre-7425-7428-7435.html?rodzaj_materialu=57 missing cyan and magenta, sent a request
• https://www.partsdrop.com/index.php...tion/developer-material.html?sfm=3&model=2067 (the eshop looks extremely similar to the previous one) Has all of them but shipping from USA at higher cost

I'm not able though to find official confirmation of the part numbers (service manual only states P/Ns for developer unit+developer). having research, I know WorkCentre 74xx uses EA-HG as does WC 73xx and that following products (phaser 7800 and WorkCentre 75xx) use EA-Eco. Still it seems they use the same developer material?

• https://www.xentair.com/xerox-workc...5-7556-phaser-7500-yellow-developer-675k67550
• https://www.xerographic.co.uk/produ...5-7556-genuine-yellow-developer-675k67550.htm

which doesn't seem to be true as this safety document from Xerox doesn't mention WC75xx: https://safetysheets.business.xerox.com/wp-content/uploads/2021/01/B-2004.en-us.pdf

Long story short : I'm ready to take all accountability you want but if I ask here is because I couldn't find all the required information or I miss the required background to unrestand them, not because I don't want to take the time/workload of doing so. hence, I have to rely on people who have more knowledge/experience to be sure I don't jump up to wrong conclusions. Thanks again!

 

And I can now confirm, it was the developer. Bought and added developer to all developer units and printer now simply prints better than ever without a glitch. Thanks a lot @adriansto for putting me on the right direction!