I found this TV last week and when I plugged it in, it momentarily came on, I was able to see the OSD, and then smoke began pouring out of the back. To most people, that would seem bad, but to me that means an easy job troubleshooting. It turned out to be the inverter transformer, and as you can see from the pictures, it's toasted. I looked on eBay and found the power supplies to be about $100. That's way more than I'm willing to spend. I also noticed that tvdoctorsalesandservice, a reputable seller that I've bought several boards from over the years, had a defective board listed for $55. ShopJimmy also had a repair kit listed, but that would do me no good. I decided to buy the defective board, I ended up getting it for $40 shipped. I didn't know what was wrong with it, but I knew it wasn't the transformer. I expected the failed components to be the ones Shopjimmy has in their repair kit, and I figured I'd just test and swap those components from my board. It turns out to be completely different failed components, but still only took a few minutes to figure it out. The first three pics are my original board. Next two are the replacement board. The IC, the resistor, the diode between them, and the diode with the red band seem to be the only shorted components and those are all OK on my board so I think I have a good chance of this being successful. I'll thoroughly test all surrounding components before powering it on. My biggest concern is what caused the transformer to burn up in the first place. It appears to be the primary side which failed. My thoughts are that it was a bad solder joint. Would I be correct in my belief that if there were ceramic caps behind the panel on this model, and they were bad, the secondary would be the side which burned? Panel sticker number is LC420WUE-SAA1.
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