LG 52LB5D TV No picture but sound.

Dylan Hicks

Honorable
May 17, 2013
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Hello, I am having a huge issue with my 52 inch LG LCD television.
One day I went to turn the television on and heard a loud pop noise. The Picture went black and the sound was on and fully functional.
I was able to touch the screen and white flashes would occur when I touched it. So I proceeded to replace the Power supply board thinking that it was a blown capacitor or something along those lines. It did not work, and I am honestly at a loss of what could be wrong. The television accepts input signals such as my Playstation 3 and plays the sound find and even flickers in and out when the game changes frames but no picture is present. Any help would be appreciated!

http://imageshack.us/photo/my-images/854/imag0237di.jpg/

http://imageshack.us/photo/my-images/211/imag0238v.jpg/

http://imageshack.us/photo/my-images/845/imag0239qm.jpg/
 
Solution


I know, but the LCD screen has a light source (like a monitor). It can be an lamp (like a projector TV), a mercury tube (like a monitor) or a LED-based lamp (so-called LED TVs have that, not to be mistaken for OLED TVs, where each pixel is a LED). I don't believe this model is an OLED. It could be one of the others, most likely a mercury lamp that lays at one side of the monitor and illuminates the screen.
You could shile a flashlight to the screen (from close distance) while the TV is powered on and see if any image is being formed on the LCD. If it does, the lamp is burned out and needs replacing. If no ghostly image is seen, then it could be the video processor and then it's a...

Dylan Hicks

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May 17, 2013
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10,510


At first I thought that this was the problem but It does not use a lamp as a lightsource. I am going to post images of it soon.
 

house70

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Apr 21, 2010
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I know, but the LCD screen has a light source (like a monitor). It can be an lamp (like a projector TV), a mercury tube (like a monitor) or a LED-based lamp (so-called LED TVs have that, not to be mistaken for OLED TVs, where each pixel is a LED). I don't believe this model is an OLED. It could be one of the others, most likely a mercury lamp that lays at one side of the monitor and illuminates the screen.
You could shile a flashlight to the screen (from close distance) while the TV is powered on and see if any image is being formed on the LCD. If it does, the lamp is burned out and needs replacing. If no ghostly image is seen, then it could be the video processor and then it's a bigger problem. I would say the lamp is the culprit ATM.
 
Solution

Dylan Hicks

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May 17, 2013
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Sorry I misunderstood. I believe it is a mercury one. Where would that be located? And what would be the average cost to replace it? I am able to put an input source and have the screen dim in and out. but no picture I see faint images in the dark with a flash light.
 

everlost

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Mar 8, 2013
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imag0239qm.jpg looks like your backlight circuit. i see resistors, jumpers, Varistors (MOV), Voltage Regulators, capacitors, balasts, and what looks like a relay. since you heard a pop. i would expect to see some kind of mark or discoloration. you may have to look on the other side of the board(s) to find it.
 

Streezybmerkin

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Sep 1, 2016
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Did you ever find a solution? Your the first person I've noticed that has also been able to touch the screen, and see a white flash. Maybe I have a similar issue. Thanks