Since you know all about safety during repair, you'll want the service manual and check voltages with your Volt meter to see if there's some power issue. Then the service manual should have a tree diagram on what board to replace in what order.
While watching our LG Plasma TV model 50P J550-UD, a poof sound was heard from the tv. It lost picture and sound. The red power light will stay lit and when trying to power up, a click is heard a couple of times but it will not start. I have tried the reset procedure that I read about using the tv power button but this did not work. I have looked inside and see no visible damage to any capacitors and have checked some resistors with a multi meter (some do not read anything) but I’m not confident in checking these. Several months ago, I had to replace the y-sustain and buffers due to a loss of picture (sound was still on). I don’t believe this is the same problem because we have no sound this time. Any suggestions?

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