LG 3D TV repair #3dtv


Dorothée H.
 

Hello,
Last night my 2016 55" 3D TV lost image. I get a 2 second view of image, then a black screen, but the sound still works. After a little research on the Net I tried: Power on the TV using control panel/menu/vol + or - but nothing. It might be a backlight problem or a motherboard issue from what I could find. 
I would like to know if anyone has had this issue? Most importantly, if I replace the motherboard or a fuse I will I not loose the 3D capabilities, correct?
I hope it is repairable. Waiting on my local repair store to call me back.
Thanks for your input.
Dorothée


Fabbian Dufoe
 

Good luck getting it fixed.  The 3D capabilities are a combination of the polarizing filter over the screen and the software controlling the display.  Replacing the motherboard might be a problem if the new part doesn't support 3D.  Replacing the backlight or related components won't affect the 3D capabilities.
--
Fabbian Dufoe
Fuji W3
JVC GS-TD1-B


Dorothée H.
 
Edited

Thank you Fabbian. I will put emphasis on the 3D aspect to the repair person and cross my fingers!
Dorothée


Depthcam
 

Take a look at this thread on the 3D Video forum.  Maybe somebody there can help you...

https://groups.io/g/3dvideo/topic/lg_55uh8500_won_t_turn_on/77310695

Francois


Dorothée H.
 

Thank you Francois. I hope it is just an issue with the backlit screen because unlike Boris, the TV turns on, the image comes, then black screen and the sound remains. One thing I got lucky is that I had my TV set on Live TV, the only way I could tell that I still have sound. If it was on Aux. mode, I would have never known. A month or two ago I had issues with the Wi-Fi loosing signal. After research, it could have been the connection inside the TV, since I didn't want to open it, I bought an Ethernet cable and fixed that problem.
I have two TV repair shops in town, still waiting on the first to call me back. I am ready to try it myself just to save the 3D.

I will let you know.

Dorothee


Boris Starosta
 

Dorothee:
The other thing to keep in mind is that the TV repair shop may or may not be correct in their assessment of the problem.  (In other words, if they say it can't be fixed, don't believe them)
I imagine the power supply board is probably good, since you still have sound.
You can check for to see if the backlight is the problem, by inspecting the screen very closely under a bright light shining on it from behind your shoulder, close to your head - the light would illuminate... should show a faint image (i.e. play a video, and see if the screen shows an image with a strong light shining from close to your eyes.  You could even use a bright flashlight.).  If you can see an image that way, then it is the backlight that is at fault.  If there is no image no matter how hard you try to see it, then probably it is the motherboard.
The motherboard is easily replaced.  Anyone can do it.  The trick is finding the correct motherboard!  See our earlier thread about that...
I had installed two "working" motherboards in my TV, before I found the correct (third) one, that was actually compatible with the 3d feature.
Boris

--

––––

Contemporary work in the Stereoscopic Arts:  www.patreon.com/retroformat
––––


Dorothée H.
 

Thank you Boris, I did the test with a flashlight and I do see a faint image. What I don't understand is the image appears each time I turn on the TV, then it goes black. If it is the backlit screen shouldn't it be black from the start? Francois did send me the thread with your motherboard replacement experience. Your patience paid in the end.
If the repair man says it is not repairable I will take it back home and roll up my sleeves, but boy this looks tedious if this is what needs to be done: https://www.youtube.com/watch?v=3oREIYgAjtI

Dorothee


gl
 


It sounds there is a fault with the backlight, where it will light briefly, but then something fails.  It could be the power supply has failed and overloads, then cuts out.  Could be other things too.

Is the backlight LED based?
--
gl

On 23/10/2021 17:58, Dorothée H. wrote:
Thank you Boris, I did the test with a flashlight and I do see a faint image. What I don't understand is the image appears each time I turn on the TV, then it goes black. If it is the backlit screen shouldn't it be black from the start? Francois did send me the thread with your motherboard replacement experience. Your patience paid in the end.
If the repair man says it is not repairable I will take it back home and roll up my sleeves, but boy this looks tedious if this is what needs to be done: https://www.youtube.com/watch?v=3oREIYgAjtI

Dorothee


Dorothée H.
 

So if it is the power supply it is around $140.
Do you mean "Is the backlight LED biased?". That I don't know for sure, I haven't open the beast yet. It's the weekend so probably cannot get hold of the repair person until next week.


gl
 

On 23/10/2021 22:57, Dorothée H. wrote:
So if it is the power supply it is around $140.
Ouch.  There may be a separate circuit board driving the LEDs, that could also be the issue.  I wonder if a capacitor failed somewhere (stab in the dark).

Do you mean "Is the backlight LED biased?". That I don't know for sure, I haven't open the beast yet. It's the weekend so probably cannot get hold of the repair person until next week.
It's a fairly recent set right?  So should be LED based.
--
gl


Dorothée H.
 

Well it was built July 2016. So yes I assume it is LED backlight. I have read that Smart TV last on average 4 years. We got almost 5 years...


Boris Starosta
 

I believe mine is LED based.  Doro, you should get the shop to replace the backlight circuitry first, that alone might fix it (the bar with the LEDs in it, is probably okay).  Or it could be part of the power supply, that supplies power to the backlight.  Anyway, based on what you say about seeing an image, your motherboard is probably not at fault.  That's good news!
best of luck!
Boris

--
––––
Contemporary work in the Stereoscopic Arts:  www.patreon.com/retroformat
––––


Dorothée H.
 

Latest news: the repair guy came and replaced the control board. Same result no image but sound, so he put the old one back. He told us that it is the screen at fault. When the back was open we could see the led turning on, then a green light flashing on the power board and all turn black. I asked if he could replace the backlight circuitry and he told me LG doesn't recommend doing that but replacing the whole screen. To replace the screen it's a $622. He finally admitted that there is a kit to replace the backlights (which I am not sure is the issue) but it costs $255 and "it will probably won't last long". I insisted that the replacing screen would be 3D, he said that would be the screen for this model. Since it's on back order with no approx. date, when will it arrive is a big question these days. He also said there's no 3D content to watch these days anyway 🙄.

Another interesting thing, he told me LG wants the defective control board back or it would charge $100 if I wanted to keep it?
We paid $95.34 for service call.
So it looks like I have to say goodbye to my 3D TV. ☹️. I am so disappointed.


robert mcafee
 

Suggest to not toss the TV.  Try searching symptoms with the new info you have about internal behaviour.

If nothing else you have a good control board you can sell and a remote control. Someone will need these. 

You can try searching Craigslist for a used model. 



Jon
 

Can I suggest you keep your eye on local 'for sale' adverts? 

I am in the UK, but here I keep an eye on Gumtree, FB marketplace etc. Many people replace their older TVs, and many of those older models have 3D capability. My last two 3D TVs have been bought that way. The first of those (now defunct) lasted several years and cost me £65, the current one is a Sony and cost me £100 and I like it very much. They were bargains, but a search for '3D TV' on Facebook marketplace right now brings up a few options close to me. Ranging from £150 upwards - I appreciate the local market may be different where you are. Almost certainly cheaper than getting that one fixed!

Another trick is to make sure you look up any likely looking models that are advertised just as a TV for sale - many people do not mention the 3D capability. Of course, you are taking a chance, there is no guarantee - but if you see it working before you pay then it's a good bet that it will be OK for a while.

Good luck!


On Tue, 2 Nov 2021 at 23:39, Dorothée H. <stereodoro@...> wrote:
Latest news: the repair guy came and replaced the control board. Same result no image but sound, so he put the old one back. He told us that it is the screen at fault. When the back was open we could see the led turning on, then a green light flashing on the power board and all turn black. I asked if he could replace the backlight circuitry and he told me LG doesn't recommend doing that but replacing the whole screen. To replace the screen it's a $622. He finally admitted that there is a kit to replace the backlights (which I am not sure is the issue) but it costs $255 and "it will probably won't last long". I insisted that the replacing screen would be 3D, he said that would be the screen for this model. Since it's on back order with no approx. date, when will it arrive is a big question these days. He also said there's no 3D content to watch these days anyway 🙄.

Another interesting thing, he told me LG wants the defective control board back or it would charge $100 if I wanted to keep it?
We paid $95.34 for service call.
So it looks like I have to say goodbye to my 3D TV. ☹️. I am so disappointed.


gl
 


That's v. shady, wanting to replace the entire screen.  Sure it's less likely that something is incompatible this way, but at that price there's a serious conflict of interest.  And 'it wont last long' is dubious at best, they just want you to pay for the whole screen.

I would try to find a local electronics enthusiast to look at it.  It may be a simple fix for someone skilled enough to troubleshoot it, ie. they might be able to just solder a part or two to fix it.  Even if they want a small call-out charge, it could be much cheaper.
--
gl

I think your best bet is finding

On 02/11/2021 23:39, Dorothée H. wrote:
Latest news: the repair guy came and replaced the control board. Same result no image but sound, so he put the old one back. He told us that it is the screen at fault. When the back was open we could see the led turning on, then a green light flashing on the power board and all turn black. I asked if he could replace the backlight circuitry and he told me LG doesn't recommend doing that but replacing the whole screen. To replace the screen it's a $622. He finally admitted that there is a kit to replace the backlights (which I am not sure is the issue) but it costs $255 and "it will probably won't last long". I insisted that the replacing screen would be 3D, he said that would be the screen for this model. Since it's on back order with no approx. date, when will it arrive is a big question these days. He also said there's no 3D content to watch these days anyway 🙄.

Another interesting thing, he told me LG wants the defective control board back or it would charge $100 if I wanted to keep it?
We paid $95.34 for service call.
So it looks like I have to say goodbye to my 3D TV. ☹️. I am so disappointed.


robert mcafee
 

while new 3D TVs are no longer available 3D capable projectors are available. In some cases a silver projection screen is required to maintain polarization (passive systems)

Berezin has silver screen material




On Wednesday, November 3, 2021, 7:04 AM, gl <gl@...> wrote:


That's v. shady, wanting to replace the entire screen.  Sure it's less likely that something is incompatible this way, but at that price there's a serious conflict of interest.  And 'it wont last long' is dubious at best, they just want you to pay for the whole screen.

I would try to find a local electronics enthusiast to look at it.  It may be a simple fix for someone skilled enough to troubleshoot it, ie. they might be able to just solder a part or two to fix it.  Even if they want a small call-out charge, it could be much cheaper.
--
gl

I think your best bet is finding

On 02/11/2021 23:39, Dorothée H. wrote:
Latest news: the repair guy came and replaced the control board. Same result no image but sound, so he put the old one back. He told us that it is the screen at fault. When the back was open we could see the led turning on, then a green light flashing on the power board and all turn black. I asked if he could replace the backlight circuitry and he told me LG doesn't recommend doing that but replacing the whole screen. To replace the screen it's a $622. He finally admitted that there is a kit to replace the backlights (which I am not sure is the issue) but it costs $255 and "it will probably won't last long". I insisted that the replacing screen would be 3D, he said that would be the screen for this model. Since it's on back order with no approx. date, when will it arrive is a big question these days. He also said there's no 3D content to watch these days anyway 🙄.

Another interesting thing, he told me LG wants the defective control board back or it would charge $100 if I wanted to keep it?
We paid $95.34 for service call.
So it looks like I have to say goodbye to my 3D TV. ☹️. I am so disappointed.


Bill Costa as just a member
 

Can I suggest you keep your eye on local 'for sale' adverts?
I agree and would add that when searching you work from a list of
desired model numbers, don't just search for "3D TV". At one point
there were so many 3D TV models on the market that many people bought
3D TVs without regard to wanting that feature -- so when listing a
used TV the seller may not mention in the listing that the TV is 3D
capable.

So with luck you may be able to find a suitable TV within a reasonable
amount of time, probably faster than getting your current TV repaired.
But... if you have the room to store a spare TV, you could still
pursue trying to get your old TV repaired -- but now at your leisure.
If you are successful, you now have a spare -- either your old TV, or
put it back into service and keep the used one as the spare.

I was lucky that my first 3D TV did not fail, but when I upgraded to a
larger one I kept the old TV as a spare. One thing to be aware of is
that, unfortunately, a working electronic device can still fail while
being stored. There are some types of electronic components that will
age over time, even when not being used. But the odds are still
greatly in your favor that it will still work when put back into
service.

...BC


Dorothée H.
 

Thank you all for your suggestions.
I am not ready to part with my 3D TV. I will not replace the whole screen but I agree there are still some other things to look at before dumping it. Last night I did check the Facebook marketplace, there were some there so I will keep looking and make some contacts too.
I will let you know.


gl
 


My best guess is that one or more electrolytic capacitors have worn out, causing the LED power supply/driving circuit to shut down.  If so that is a relatively easy fix for someone with experience.

Electrolytics do wear out, unlike other types they have a liquid inside that can dry up over time (accelerated the hotter they get in use).  The better capacitors should last longer, but often manufacturers cut corners, given them a relatively short lifespan.

If that's what it is, usually replacing the faulty ones can completely restore functionality.  It sounds like that kind of problem (as the light is turning on briefly).
--
gl

On 03/11/2021 15:07, Dorothée H. wrote:
Thank you all for your suggestions.
I am not ready to part with my 3D TV. I will not replace the whole screen but I agree there are still some other things to look at before dumping it. Last night I did check the Facebook marketplace, there were some there so I will keep looking and make some contacts too.
I will let you know.