LG 47LS4500 blacklit, no picture with sound

[jamcnabb]

I have an LG 47LS4500. When I plug it in, I get the red power LED, and when I turn the power on, the display appears backlit, but no images come up and I hear static as if it were set to the cable coax input with no signal.

I have a blu-ray player plugged into an HDMI port, and if I click through the inputs, using the remote eventually I stumble onto the correct input (since I can't see any menus) and I can hear the audio from the movie in the blu-ray player.

I've checked the boards in the TV and did not see any obvious problems.

Any thoughts for things to check are much appreciated!

Thanks,

Andy

[sordids999]

Re: LG 47LS4500 blacklit, no picture with sound

Posting pictures of the back of your tv showing the boards with clear pictures may help you more with fixing your problem

[Seanl84]

Re: LG 47LS4500 blacklit, no picture with sound

Is there an av out on the set Andy? If there is you could probably connect it to a monitor or another tv to see if the problem persists.. If it does it could point to main board fault, if not maybe t-con..

[jamcnabb]

Re: LG 47LS4500 blacklit, no picture with sound

Pictures of the boards:

There are no video outputs, only an audio output.

I noticed this morning that while the TV is off, the red LED is on indicating power, but when I click the power button on the remote, the LED blinks 3 times, then goes off and the TV is backlit on with static.

Is the blinking of the LED indicative of a power issue?

thanks again for any assistance!

Andy

[Seanl84]

Re: LG 47LS4500 blacklit, no picture with sound

Have you a DMM? If so check the DCV on either side of this smd fuse on the t-con

[jamcnabb]

Re: LG 47LS4500 blacklit, no picture with sound

I do have a basic DMM. Continuity was good and measures 11.9 V on both sides of the fuse

[ReeceyBurger123]

Re: LG 47LS4500 blacklit, no picture with sound

Im going to throw my 2 pence in now, I recon your Lcd panel is failed. Seen about 5 Led Tv's with sound, backlight no image been failed Lcd modules and guess what one of them was this exact Tv !

Take it apart down to the tab bonds and check if they are getting hot or if one is colder than the others if so you have a failed tab bond driver which was the case on mine.

[budm]

Re: LG 47LS4500 blacklit, no picture with sound

Try having one cable between T-CON and LCD panel connected one at a time to see what you get.

[jamcnabb]

Re: LG 47LS4500 blacklit, no picture with sound

So I got to the tab bonds. I left the TV on for a bit, but never really felt any excessive heat from any of them, nor any one of them that was cooler than they others.

I did happen to find what looked like some corrosion on the driver board near one of the tab bonds. I used a plastic brush to try to clean it off a bit, but it didn't help anything.

Based on other threads I've looked at (and linked youtube videos), if I had a tab bond issue, I'd expect either distortions on just one or both sides, rather than a completely blank screen. Even the corrosion, (if that's even related to my problem) I would have expected to have that side of the display having issues.

I already replaced the T-CON board because based on my initial research on the threads seemed to be the most logical problem (and the cheapest fix), but replacing it has not fixed the problem.

Thanks budm. I disconnected the left side, and nothing was different. I reconnected the left and disconnected the right side, now the left side of the display has colored lines and the right side is white.

What does that indicate?

[ReeceyBurger123]

Re: LG 47LS4500 blacklit, no picture with sound

Failed panel unfortunately

[ReeceyBurger123]

Re: LG 47LS4500 blacklit, no picture with sound

How do you mean corrosion too ?

[jamcnabb]

Re: LG 47LS4500 blacklit, no picture with sound

Just that near one of the connectors I saw suspicious white chalky material, like some water had been spilled on the screen and ran down to the bottom - with the kids using the TV for a games it wouldn't surprise me one bit.