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Hey,
I am still learning basics of in depth repair of laser printers and recently got Laserjet Pro 200 Color with some problems.
I was said that colour toners were working fine but were super low. Black toner was half full and fully broken, demo page was 100% black on front and just dirty on back. I have tried everything: change of charge rollers, drums, dosage blades, cleaning blades in any combination (all used) - nothing.
Toners are placed in the tray in this order:
-- BACK OF THE PRINTER -- Y: Chinese knock off - faulty? M: Chinese knock off - faulty? Y: re-manufactured HP K: re-manufactured HP -- FRONT OF THE PRINTER --
Idea: Was simple, replace Black and refill colours with genuine HP toner bought from old stock.
1. Black toner
I was trying to find out what happened with black toner that it was working for some time then suddenly stop. I have tried different combinations of used drums, blades etc.
Prints were 100% black. Transfer belt had a thick layer of black toner. All of the clean toner was finding it's way into colour waste toner thus needed to be cleaned.
Technically after all the changes I had two different cassettes. Didn't worked and I did not wanted to buy brand new blades and drums just to experiment.
I was able to find newly re-manufactured HP black toner with green drum (rest were blue). Works fine.
2. Colour toner
As the first cassette I filled cyan HP one as it required disassembly due to no fill port. Cassette was fully cleaned. After further inspection I can say that rollers have no long to go, but drum was fine, apart of that no signs of damage. Filled with 30g of OEM HP toner for test. Demo print looks perfect (in black and cyan).
Then I took two yellow and magenta Chinese knock offs apart to clean waste toner that was full of previous black toner. No damage of either of two. Filled again with ~30g of OEM HP toner for test. Demo print have vertical Magenta/Yellow stripes.
3. Checking for damages
Next step was to check magenta and yellow cassettes again. Drum, rollers, blades and all contact points were degreased with IPA just to be sure. After few demo prints I have found that there is quite large amount of toner in waste compartment of both toners - like 1-3g while waste toner was cleaned a few prints ago.
4. Checking belt and 2nd transfer roller
Just to be sure I have dismounted transfer belt and second transfer roller from the printer. Belt was degreased with IPA, colour sensor purged with some air, belt blade and brush cleaned as well. Second transfer roller looked like a rainbow - cleaned.
After all of this, colour calibration was done and this is how demo page looks like. Please note that only magenta and yellow lines are visible. Cyan toner works fine. Lines overlap on front as well as on bottom. Full quality images available on my Imgur: Imgur: The magic of the Internet
scan_Strona_1 90.jpg
scan_Strona_2 90.jpg
Now, I am fully aware that the problem here are these Chinese cassettes, but I am trying to understand what exactly is the cause. Replacing those two for a brand new cassettes if out of equation. This printer will be given away so I am not really keen to pay extra.
Cassette is made of two assemblies - toner delivery assembly and waste toner and developer assembly. Toner delivery assembly (toner compartment, doctor blade, charge roller) looks absolutely fine on both yellow and magenta cassettes. Clean toner layer is thin and even.
For me the waste toner and developer assembly is the problem here. Although it looks like waste toner silicone blade is working fine as the drum is clean after several passes that does not explain why both ITK has signs of toner and second transfer roller looks like a rainbow.
Is it that drum is overexposed/expired? I have no info for how long printer had these cartridges installed - could be even years.
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Originally Posted by Wild Bill
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