LG 47LN5400-UA LED picture has gone out. Audio works. Using flashlight I can see faint menu image. LED Driver or LED Strips? How can I tell?

Chances are it's bad backlights if you can see the image with a flashlight

check voltage on tv psu output

Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://homenol.blogspot.com/
http://electronicshelponline.blogspot.com/
http://electro-medical.blogspot.com/
For some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced. To some models of sets, all these section circuit will be integrated at its main board. If this is the case, you have to replace the main board.
Search the site by type in the "brand name" to your device; [Exclude the model number], in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.
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replacing the led's is not so hard and could be a lot cheaper, you only need to replace the bad led not the whole strip, you can get them on ebay

The led driver AND the T-con board are bad. If you could see a picture with the flashlight then the T-con board would be good. It is not. The led driver can be on the main board or the power supply board. You can get these parts from here: TV Parts Universal TV Stands DLP Chips ShopJimmy

This is a common problem for LG 42LN5xxx & 47LN5xxx LED TVs, the problem is defective LED back lights strips, it has nothing to do with main power supply & the main board.

hi yes the led have shorted out thanks

shaun

Please replace the LED back lights strips.

This could be the power supply at 55 dollars or the LED back light strips that are about 80. Unless you know how to test them, it is a toss up. Most of the time it is the led strips though. http://www.shopjimmy.com/lg/55la6200-ua

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