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Electronics => Repair => Topic started by: gardenal on October 02, 2016, 05:37:55 pm

Title: LG 32LH20R No sound and screen
Post by: gardenal on October 02, 2016, 05:37:55 pm

I am new on fix eleronics. My LG 32LH20R just died after a few second from turn on. It looks like I have replace the mainboard but I just want to be sure. The powersuply board looks ok and the mainboard is receiving the right voltages. The LED and background light works.

Any one can help how to confirm if the problem is on mainboard.

Title: Re: LG 32LH20R No sound and screen
Post by: chavotronic on October 03, 2016, 08:30:16 pm

Quote from: gardenal on October 02, 2016, 05:37:55 pm

The powersuply board looks ok

What make you think that the supply is ok? What and how did you check it?

Title: Re: LG 32LH20R No sound and screen
Post by: wasyoungonce on October 03, 2016, 09:33:17 pm

OP I think you will find most LG TVs and monitors suffer from what is known as the "Bad caps plague". (http://badcaps.net/forum/showthread.php?t=18679).  Also looks to have an issue with some zeners on the PSU board.

If your search the net you should find diagrams here  (http://lcdrepairguide.com/V4/2014_Bonus-V4.0/LCD-LED-TV-Power-Supply-Schematic-Diagram.html) or here  (http://elektrotanya.com/lg_32lh20r-ca_09p-lcd2632_psu_sch.pdf/download.html).

SO measure the PSU and post back on the results.

Replacement supplies are available just search fleabay or such like.

Brendan