Recently our Dynex DX-42E250A12 42" LCD TV stopped responding. When we shut it off, we could not turn it on. The standby LED remained lit, but there was no response to the "on" button. I have a smattering of electronics experience, and I've replaced things like fuses and caps on circuit boards before, so I took it apart to see if I could find a problem. The TV is easy to disassemble. There are only three boards inside. The power supply board is the only one that has non-solid caps on it. I could not find any that were bulged, and the fuse tested good. Connections all looked tight, and I could see no evidence of cold solder joints, no hot spots, etc. I put the board back on and plugged the TV in, switched it on. It came on, but I heard a faint cheeping, and after a few seconds, one of the caps on the power board started smoking, and exploded. I did nothing to the board, there were no shorts, etc. I'm wondering what might have caused this? A bad voltage regulator? The cap that blew was the largest one, on the far left in the picture, a Rubycon 82uF 450V capacitor. I've found a new board for it, but I'm hoping the fault here is confined to the power board, and not something else.
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