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Equipment Repairs => PLASMA TV forum => Topic started by: jestah on February 27, 2013,18:21:24

Title: LG 50PC55 PSU Schematic or advice please
Post by: jestah on February 27, 2013,18:21:24

Hi,

I've been suffering with a LG 50PC55, it came in with the standard bulging caps, as per the available repair kit (6x 3300uf 10v + 680uf 50v) - I did those, but no joy

its board numbers are: 2300KEG006A-F EAX32412301/6 YPSU-017A EAY32957901

I get the just over 5v across the replaced caps, but nothing at 5vsb pins
I can see that the supply for the 5Vsb reaches U233, but it's not being switched on

I'm suspecting either U701 controller or signals to it, but without a schematic it's a tad tricky!

If anyone has suffered similar or has a schematic, I'd be most grateful for any offerings

Cheers,
Si

Title: Re: LG 50PC55 PSU Schematic or advice please
Post by: fix2003 on February 28, 2013,02:53:24

check transistor Q953 (2sc3198) is not s/c
had a set with this gone also

Title: Re: LG 50PC55 PSU Schematic or advice please
Post by: jestah on February 28, 2013,05:09:17

Thanks for the reply, I've just checked that, it's good and healthy...

Any other ideas?
Many thanks