Question

LG37LB1DA-UB

TV powers up and back lights but no picture or sound.
Replaced PSU and TV worked perfectly for approximately 10/20 minutes and reverted back to "powers up and back lights but no picture or sound".
In inspecting newly installed PSU identified capacitor C210 with bulged top and minor leakage which is likely the problem.
However, in checking the output voltages from this PSU board with bulged capacitor all outputs appear correct as marked on board.
Ideas / suggestions please.

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Answer
More than voltage.

While any bulged cap is a failure to me and most techs, you can't go with a voltage only reading. Those capacitors smooth out the ripples in the supply and you would need an Oscilloscope to really see if the supply line was good.

Today's techs just swap boards. Some replace caps.

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Thank you for your prompt answer

Thank you... I'm a novice and do not have an oscilloscope.... I thus mostly 'pluck and chuck' but this was a replacement board I had installed and now I'm second guessing myself wondering if there is a problem somewhere which is 'causing' the cap failures on the PSU?
OR did I just purchase a board on the verge of going bad?
The original PSU I believe to have been damaged by surging of our electrical power during a recent thunderstorm.
This replacement I have no explanation.
Any input is appreciated.
Thanks

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It gets worse.

Sorry but a failing/failed/lightning struck TV can lose almost every board. HOWEVER google this ->>>>>> BAD CAPS

The cause was industrial espionage gone wrong. In over 2 decades I've yet to find it a fault of the design or TV maker.

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:(

FYI, no harm no foul and your help and suggestions and thanks again and yes, I have read 'bad caps'. I am not positive of damage from the surge as the TV actually worked for about 24 hours after the storm.
I actually googled my issue and found dozens and hundreds of posts and watched several videos regarding the history of cap failures and the replacing of caps. I have two boards now and I may replace the bad cap on the newest PSU with a cap from the original and see what happens.
If I may... one more question... please bear with my electronic ignorance... (my degrees are in business and history)... on the main board when I plug the TV in, five LEDs light up.
Four are a lovely shade of green, HOWEVER one is a dastardly red...
Is as is in most cases red a bad sign, a sing of a failure and or damage?
I can return the newest PSU and get another and I'm thinking of also purchasing a main board.
Again, a thousand pardons for my ignorance of electronics, I am a self taught jack of all trades.
Happy

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To figure out those "codes"

I need a service manual or a TV tech that has happens to work on such a model. For non TV techs my advice is safety first (voltages inside can kill) and then when swapping boards when you're not sure, change the cheapest one first.

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:) Thanks again

No worries, safety is always first... my first semi training in electronics was during college when I worked at an electronics store. I'm sure you remember, tubes and fly back transformers.. lol
With this set I have already once 'plucked and chucked' the PSU approximately three years ago when this TV first failed. Then it was simply bad caps in the PSU.
I'll probably just return this most recent PSU, get another and a main board and take a shot at luck... lol
Thanks again

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