Re: 42LG50 Won't Turn On



Here are photos of the power board....

Re: 42LG50 Won't Turn On



How would I do that? Do I need anything more than a multimeter?

If I were to test for those commands and find that they are being sent from the main board successfully - would that prove that the problem is with the power board?...

Re: 42LG50 Won't Turn On



Haha, something like that. I was more thinking that maybe there was a way to disconnect something and test the power on the main board, etc. I'm a programmer and I'm approaching this like that - trying to be able to identify roughly where the problem is, so I can focus my testing....

Re: 42LG50 Won't Turn On



WARNING: Likely obvious newbie question coming up!

Is there a way to, at a high level, determine whether the main board is good by measuring something on the power board (which appears to be next in line)?...

Re: LG 42LG50 Won't Turn On



I'm a quick study but I fear that my lack of (really any) knowledge in this area is catching up to me. I can see that the formula to determine the output voltage of the 5th pin is 1.200(R1 + R2) / R2, but I can't figure out how to determine the values of R1 and R2.

I understand that those values correlate to the resistors that you circled (they are actually R716 & R717, not what you had written) but I'm not sure how to determine those values. I searched the datasheet that you provided as well as the internet in general...

Re: 42LG50 Won't Turn On

Thanks for your help and the clarification about the adjustable regulators, that makes sense.

I'm going get the readings on the rest of the regulators this morning, but was wondering if you could tell me if the TV symptoms (won't turn on, but standby light will) are even consistent with a bad regulator in general?

SUMMARY
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An LG 42LG50 that won't turn on (though the standby light does turn on).

WHAT I HAVE DONE
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I'm totally new to this so I'm sorta fumbling around as to where to go. I ordered a replacement power board, but wanted to see what else that I could do while I awaited it. In research, I found that often times a faulty main board is to blame, so I wanted to see if I could figure out if that were the case with mine.

I went through the instructions located in [URL="https://www.badcaps.net/forum/showthread.php?p=261329"]this...