KDL-32BX300/APS-252 blows fuses

[kturnerga]

I got a KDL-32BX300 Sony with a bad power supply. The fuse was not blown. No LED or anything showed up and the standby, etc pins on the supply tested a big fat goose egg.

I ordered another APS-252 power supply. It arrived yesterday. I installed it, plugged the TV into the outlet and POW! I ohmed the fuse and it was blown. I replaced the fuse and when inserting the line cord I saw a flash and heard POW!

I noticed the cord has a little kinking but I had tested it (so I thought) and the analog meter tested that it was giving the board power.

If this board has a rectifier where would it be? This is what I hear is a fault in some power supplies.

[budm]

Re: KDL-32BX300/APS-252 blows fuses

No idea until we get good clear pictures of the boards and the whole back side of the TV showing how all the boards are connected together. So right now you have two bad power supply boards?

[kturnerga]

Re: KDL-32BX300/APS-252 blows fuses

Yep; both are bad. One was with a good fuse but would not show a power good LED or show any standby voltages. The replacement would blow fuses and not show a power good LED. After the fuse replacement (and this should simplify things) I had nothing but line voltage and the ground screw wire in the corner of the board for connections. It was bolted to the chassis. I plugged in the voltage and POW!.



https://www.flickr.com/photos/746549...posted-public/

https://www.flickr.com/photos/746549...posted-public/

Sorry; had issues with adding the image so I had to do hyperlinks.

These are views of the replacement power supply board that blows fuses. The other power board looks the same.

One more thing; Is the four-legged chip on the heatsink the bridge rectifier? I tested it on both boards and am getting different readings with the DVM on diode setting. I'll send you readings later when I retest.