Question about Dell UltraSharp 1800FP 18.1" LCD Flat Panel Monitor

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I have a Dell 1800FP monitor. I get no power lights at all

I have opened the unit up for a quick inspection of the power supply and here is what I found.

I have checked the AC through the full wave bridge - it is good.
I have 165 Vdc all the way until Q902 ( which I am assuming is a SCR??

Could the problem be in IC 901??

Does this power supply need to be loaded to get the 5 and 12vdc outputs??

I have hooked it up on a bench with no loading.

Any help or schematics of this thing would be appreciated

Thanks Rob

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  • oceanaccess2 Jan 29, 2009

    why is it so difficult trouble shooting a power supply?
    I can do it without a schematic by ohming out the components one by one if necessary. A schematic just makes it that much easier. Once it gets to an IC and not a discrete component then that is a different story. I would rather replace a $1.00 transistor than the entire powersupply



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finding the fault in power supply is bit difficult , as it either works or goes bad . You can check this website for reworked power


Posted on Jan 29, 2009



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