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Russell H.
Russell H., Computer System Tech
Category: Computer
Satisfied Customers: 12065
Experience:  11 years experience
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Samsung Printer SCX 3400 does not print - error message

Customer Question

Samsung Printer SCX 3400
does not print - error message says check the LSU.
What do I do? Thanks!
Submitted: 2 years ago.
Category: Computer
Expert:  Russell H. replied 2 years ago.
Hi, thank you for contacting My name is Russell. I will do my best to provide the right answer to your question. I'm sorry to say that, if not hopeless, this is at any rate a case with some grave possible outcomes. The LSU is the laser scanning unit. It is the 'laser unit' in other words, inside which the laser beam is emitted and the polygon motor and the spinning mirror are contained. The warning about the LSU, means you may have toner / dirt / dust upon the glass surface on the exterior of the laser unit. This glass surface is also known simply as the 'window'. Turn Off the printer. Unplug it from the power. Open it up and find the 'window' on the laser unit... the laser unit always has a large warning emblem on it, which basically says, "Here's the laser beam emitter... be sure to unplug the printer for a while before opening it to this region, since the laser beam is powerful enough to damage eyesight. Unplugging the printer makes quite sure it won't be active, not even slightly."That warning label should help identify it.Clean the glass 'window' on the laser unit, with a clean, dry, lint-free rag cloth, by wiping it fairly firmly.Close up, plug in, turn On, see how it goes.
Customer: replied 2 years ago.
Oh MY! ok thanks -I will do this
Customer: replied 2 years ago.
or leven that the unit was unplugged from power while being connected to the mac.The paper comes out blank --
Expert:  Russell H. replied 2 years ago.
You may have to reinstall the driver on your computer. Other things may be wrong, instead, or also. Did you put all components back properly? did you by chance wipe the gleaming metallic 'drum' surface? if so, that's a grave mistake, and has ruined the drum.
Customer: replied 2 years ago.
I only wiped the flat surface where the paper goes. I couldn't find what you were referido to. So I couldn't open it either. I'll try to re-install.
Expert:  Russell H. replied 2 years ago.
1. unplug the printer from the computer2. go to the printer's list, select the printer, then delete it with the - button.3. restart the computer4. add the printer back in to the printer's list.
Customer: replied 2 years ago.
Customer: replied 2 years ago.
did all that - the paper feeds fine but no print.
Expert:  Russell H. replied 2 years ago.
Did the error code go away? Did you go through all 4 steps I recommended?
Customer: replied 2 years ago.
yes - there is no error code. The paper feeds through as it should but no printing ocurre
Customer: replied 2 years ago.
Toner is 50%
Customer: replied 2 years ago.
any other ideas?
Customer: replied 2 years ago.
thanks anyway - have to go from the desktop now. Will check later
Expert:  Russell H. replied 2 years ago.
Can you do any sort of self-test, or Configuration, page from the printer itself alone, as opposed to from your computer ? if so, please try that and tell me what result you get. Also, open the printer again. Look for the shiny bluish-metallic-looking, 'drum'. The 'window' should be near the 'drum'. The window is just a sheet of clear glass on the side of a laser unit, and it faces toward the shiny bluish 'drum'.