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Question

42LG5020 backlight broken

Apr 23, 2014 6:13AM PDT

Hi,
My 42LG5020 HD LCD tv backlight appears to have just broken. Do these tv's have a backlight that can be replaced?
I am reading that inverters are a common fault on these tv's. However, all the stories report that they loose the image but they can still hear sound.

My problem is the tv went dark, like somebody had turned the backlight off, turned the brightness down and the contrast all the way up. I have a picture, its just dark, red and rubbish. The sound is un-effected.

Has anybody experienced this problem or does anybody have any advice?

Kind regards,

Lars
UK

Discussion is locked

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Answer
There are videos about this area.
Apr 23, 2014 7:27AM PDT

But you as the TV tech would know what the service manual has to say about how the light works. Here's a handy link where a TV tech shares. Notice they didn't really fix it? More of a band aid.
-> http://www.youtube.com/watch?v=2WNzc9zgTzE

As you are the TV tech, you get the service manual and use your prior works to lean on. Today we can see if anything pops up on the web as well.

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thanks for your help
Apr 23, 2014 6:49PM PDT

Hi,
Thanks for your reply. I am not a TV tech. Is this forum for tech's only? I thought I could just ask for help. The video you sent was helpful, but that was for tv's with no image. Mine still has an image, I can watch it, it is just like watching it through sunglasses with the contrast turned way up.

I have narrowed the problem down to the backlight. No matter how high or low I adjust it on the TV, the picture stays dark, grainy, flickering and with too much contrast.

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Re: backlight
Apr 23, 2014 7:04PM PDT

Since the user manual doesn't mention how to replace the backlight, it's considered by LG to be not user serviceable. That's why you need to call a tech to do it or play for tech yourself. That last option is what Bob tried to help with, but if you feel not confortable with the idea only the first remains.

Kees