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Problem with LCD inverter board

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Spork

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Hello, I'm not sure if this is the correct section, but it seemed the most relevant.

I've got an LCD monitor that turns on and displays a picture very nicely, for about 3 seconds before the backlight turns off. Now, since I get a nice display, I can assume that the actual light bulb (cold cathode) is working fine and the inverter board is the part that is failing.

Now I know it is cheap to replace the whole board, or the whole monitor in this case, but I am looking to understand what part(s) would be failing. I want to say it is a capacitor issue, but I've got several capacitors on the board and none are bulging, I was wondering what I should do to test or what other parts I should suspect. (I've got a rework station and multimeters, but no o-scope yet, so my testing may be limited)

Any help would be appreciated,
Spork
 

lcd inverter capacitor

I am working on a Benq 17" FP737s LCD monitor. I have no Backlights at all.
There are four total, two top, two bottom.
When i look at the circuit, i find no voltages at all in the backlight inverter section
which is the same pcb as the AC power board.
I have no schematic, so i am drawing me one. Slow process!
I am at the AC bridge section, which measures at 164 VDC at the filter capacitor.
So far so good.
My point to you, is you are going to have to dig in and look at the circuit physically
and logically(schematic).
Post any observations.
 

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