LaserJet print is "smudged"

Philip Gwyn

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Hello,
I have a LaserJet 4050tn that I love. However, it developed a problem : prints are coming out smudged. The page has a fine layer of toner on it. The layer is blotchy and mostly vertical. This toner can be removed with a normal white eraser, where actual printed content can't be.

I like this printer and hope I can repair this. However, I don't know which parts need replacing. Rollers were replaced 2 years ago. My toner cart is low, but I'm hesitant to replace it if I can't fix the smudging first.

Thank you,

-Philip

Picture of a print :
drK3bEt.jpg


Back of the page :
JG1tyEk.jpg
 
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The Hat

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@Philip Gwyn, the general consciences are the drum on your printer has been damaged and/or is near the end of life, here are a few things you can try to revive it.

I know your printer is different than the one depicted, but the principals are the same and its only to give you some idea on what to do with your own...

Start with the grey background as in the first Pic, Fig 1.
Fig 1.PNG click to enlarge..

Cleaning the Corona wire, Pic Fig 2.
Fig 2.PNG

Cleaning the Scanner Window, Pic Fig 3.
Fig 3.PNG

If none of these suggestions work then you’ll have to invest in a new Drum, sorry...:(
 

stratman

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Philip Gwyn

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Thank you for the reply.

"The drum" would that be the one in the toner cart? Because an exploratory investigation show that to be covered in toner and streaked. What's more, the transfer roller is also covered in toner.

160 $ for a fuser assembly and 150 for a new toner cart for a printer I paid 20 $ for 7 years ago? IMHO worth it if I get another 7 years out of it. I'm going to do more research on where the corona wire in an LJ 4050tn is.
 

Philip Gwyn

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Flipping through the service manual, I see that the main drum is in fact part of the toner cart. Which leads me to believe a new cart and transfer roller is all I need. Also, I assume that Static charge eliminator is the corona discharge wire that @The_Hat talked about.

ibbpCSM.png
 
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sparky

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Hello,
I have a LaserJet 4050tn that I love. However, it developed a problem : prints are coming out smudged. The page has a fine layer of toner on it. The layer is blotchy and mostly vertical. This toner can be removed with a normal white eraser, where actual printed content can't be.

I like this printer and hope I can repair this. However, I don't know which parts need replacing. Rollers were replaced 2 years ago. My toner cart is low, but I'm hesitant to replace it if I can't fix the smudging first.

Thank you,

-Philip

Picture of a print :
drK3bEt.jpg


Back of the page :
JG1tyEk.jpg
hi i have had this problem before it usually is the fuser unit that is the problem if i'm not mistaken it uses a teflon film instead of a teflon coated rubber roller. the film may be damaged and will need to be replaced
 

Philip Gwyn

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Printer is now giving an 40 EIO error, meaning the jetdirect board is having problems. Which means the mainboard could also be having problems, causing the smudging problem. I think it's time to put this printer out to pasture.
 
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