when i first got this tv it turn on then off. when i openned it found that the backlight wirers were shorted out and the heat spots by the diodes i test the diodes they were good and fix the wires. now the tv worked but there was a loud squealing that would go away in 15 minutes. i thank it was coming from the transformer on the small power board. the tv work like this for two weeks until i took out the power boards and when i put them back in now the tv turns on then off again.
emerson lc320em82
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Re: emerson lc320em82
I've got a sylvania LC320SS9 in my basement with a broken screen. The power supply is roughly the same as yours. If i unplug one the bulbs the tv will turn on with the backlight for 2 seconds then shut back off to standby. So your issue is either a bad bulb or one of the transformers.
You can check the transformers with your multimeter in the OHM setting. Unplug each bulb and put the probe on the 2 pins on the power supply's ccfl connector. Post your results.Comment
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Re: emerson lc320em82
Could be a bad cfl, or failing caps on the psu.
I would bet on inverter side of it.Do NOT touch heatsinks when testing for voltages as they may be LIVE!Comment
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Re: emerson lc320em82
Mr Bill beat me to it, your psu is probably sensing that summat is not right so is switching off, i had a similar problem with a tv i bought, took the inverter board out, seen no problem, unplugged the cfls, plugged them back in, and hey presto its alive, been watchin tv on it for over 2-3 month.Do NOT touch heatsinks when testing for voltages as they may be LIVE!Comment
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Re: emerson lc320em82
This might be another issue we may have to address after we solve your shutdown issue. When you repaired the wires was is because they were melted or cut? Does the noise specificly come from T2 if that bulb is plugged in?Comment
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Re: emerson lc320em82
(t2) makes more noise than the other transformers but it sill light up its backlight and all the backlights work. t4 was the the transformer that the wires melted and shorted together but when i fix that the tv work for the two weeks untail i remore the power boards to test them and when i put them back in the tv did workComment
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Re: emerson lc320em82
Maybe check the solder joints on the transformers. If you had a spare bulb i would plug it into T2 and see if the backlight would stay on. You might be able to swap T1 & T2 bulb connectors and see if the noise moves to the other transformer. It looks like from your pictures there is enough slack.Comment
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