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

Posted by on

  • 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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  • Dell Master
  • 1,183 Answers

Hi,
finding the fault in power supply is bit difficult , as it either works or goes bad . You can check this website for reworked power
supplies.
http://resurrectek.com/osCommerce/

Thanks
proton

Posted on Jan 29, 2009

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Replacement power supply module:
http://lcdrepair.us/1800fp-power.html

Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
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Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm/

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Capacitors kit: http://lcdalternatives.auctivacommerce.com/ he can make you a set of caps for you.

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I am facing a problem with my SMPS. When I press the power button, the LED, SMPS fan and processor fan turns on for a moment then goes OFF. I looked at SMPS PCB and found tht big capacitors had a chemical...


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http://www.lcdrepair.us/1800fp-power.html

http://www.lcdrepair.us/1800inverterKUBNKM045A.html

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