Need help with my SONY KV-27V22 TV please (burning smell after turned off and TV now dead)

Hello,

I turned the TV off at night and tried to go to sleep. Everything was working perfectly with the TV and it had been working perfectly that way since I bought it (9 years ago!). There was no malfunction indication of any kind (bad picture, bad sound, smell, etc.) before I turned it off. After I turned it off for no more than 5 minutes, I heard a loud sound like something bursted (sounded like "pak!") and there was burning smell coming out too. I believe there was a flashing light coming out too -- but not sure because my eyes were closed and the loud sound may have caused the brain to imagine the flashing light. It was late at night and I figured it must be a blown capacitor or resistor. In the morning, just by curiosity, I tried to turn it on with the remote controller and it didn't turn on. No sound, picture, red indicator light, or relay clicking or anything. I tried to push the ON switch on the unit directly and there was nothing -- complete quiet. Obviously there was no power feeding anything. I made sure by unplugging and plugging in. While plugging in, I observed a small spark at the outlet too (just like when you plug something in and you occasionally see a small spark). Looks like there was still power circulating on some part of the circuit.

I opened the back cover, removed the circuit boards, and tried to find a blown component. I tried for a few hous but to my surprise, all circuit elements appear to be 100% inact! The only fuse in there is also not blown. There was no indication of what may have bursted at all. Everything looked clean or evenly covered with a thin layer of dust. The picture tube and the copper coil looked ok -- no burn, broken, or anything. Do you think it's the flyback transformer? From my understanding, it generates most of the other voltages used in the unit. Or anything else I should be looking at? I'm still wondering where the burning smell came from. Thank you!

Reply to
doonyapong_w_8
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I'd guess a capacitor in the power supply section. It will certainly not be the yoke or flyback, those are not powered up with the set off. Trace out the standby PSU circuit, it shouldn't take long to find the bad part. Check all the semiconductors in that path, one or more may be shorted.

Reply to
James Sweet

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