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Bob Engelhardt Bob Engelhardt is offline
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Default Power supply for back light of LCD monitor

I have an HP Pavilion f1903 19" LCD monitor that has gone bad. The
symptoms are a blank screen and a flashing power light. Google finds
are pretty consistent that the problem is with the inverter board
supplying the back lights. My DMM shows a few volts on the 4 outputs -
not the "high" voltage warned of.

Google found this page that describes the fix(es):
http://h30434.www3.hp.com/t5/Desktop...een/td-p/12212
or
http://tinyurl.com/95d3xw7

It says first look for cold solder joints. I couldn't find any, but my
eyes aren't what they used to be, even with a magnifier 8-(. Then,
bulging caps (none of those), replace them anyhow. And, "might as well
replace the power transistors while you're at it".

If that's what it takes, it's not so bad (4 caps, 4 transistors, on a
single-sided board). But I'd rather a more methodical approach that
would actually identify the bad part(s), since I don't have the
replacement caps & transistors.

Your advice would be appreciated,
Bob