LG LED TV white spots

[hub...@ccanoemail.com]

Anyone with experience or helpful advice on this -
2 ~ bright / white spots have appeared on the screen of our
42 inch LG LED TV

LG 42LF5800 Sept. 2015

Various google and youtube searches < as per usual >
seem to lead into a rabbit hole of no return ...
.. from cold re-starts to software / firmware updates
to energy saving settings
to pulling it apart and re-attaching the lenses on the LEDs ..
I'm hoping to find a best-guess or diagnostic trick
from someone who has been-there-done-that ..
John T.

[hub...@ccanoemail.com]

On Wed, 12 Jul 2023 07:34:01 +0100, Charlie+ <cha...@xxx.net> wrote:

>On Tue, 11 Jul 2023 17:35:38 -0400, hub...@ccanoemail.com wrote as
>underneath :

>From experience a dark LED is much less noticible/ annoying than bright.
>Apart from a new TV and assuming the bright LEDs are permanent and
>unmoving - try blocking them out with the finest permanant marker you
>can get. You can always reverse out with some meths.. C+


Thanks for your reply.
The white spots are ~ 2 inches in diameter and look
like the TVs in the youtube videos that have had the
lenses / diffusers fall off. It would be nice to have a way
to confirm this diagnosis before an attempt at DIY repair.

This video shows the guy tipping the TV side-to-side
and listening for the lenses sliding around -
I'll try that.

https://www.youtube.com/watch?v=Tv5s0KttNX0

Any other tips or advice from someone who has done this
is appreciated.
John T.

[ohg...@gmail.com]

Very common - these drop lens. You have to remove the screen and pick up the leds and glue them back in position. The position is more critical on these than most types. These use the top hat type lens instead of the dome type. With the back light on, glue the lens directly over the LED die or you'll get hot spots on the screen. By the time you get the screen apart, you'll probably discover more have fallen off just from moving the TV around.

You'll have to stabilize the other ones that are still in place because the UV light from the LEDs embrittle the adhesive. I use clear RTV and put a tiny drop on each and every lens. You may find that when you touch the RTV to the lens, the lens may displace or fall off. If so, recenter it properly.

If you like the TV and plan to keep it for years, then a better option is buy a set of LED strips with the attached lens and replace everything behind the screen. More money but you won't have to worry about lens alignment or LEDs that might fail in the future.

This series is also an LED killer, so when you're done, lower the back light adjustment, particularly if you're just resetting lens'.

[hub...@ccanoemail.com]

On Wed, 12 Jul 2023 11:58:03 -0700 (PDT), "ohg...@gmail.com"
<ohg...@gmail.com> wrote:

Thanks for your reply.
I had to look-up RTV - I would have used epoxy.
Do you also RTV to re-attach the fallen lenses as well as
to secure the still-attached lenses ?

RTV as in this product :

https://www.canadiantire.ca/en/pdp/j-b-weld-clear-rtv-sealant-3-oz-0383793p.0383793.html?rq=rtv#srp

Or is there a specialty product that you are referring to ?

John T.

[ohg...@gmail.com]

I use the RTV because there's no significant strength required, it's clear so it doesn't cast a shadow from the lens, and it's easily reversible if you should make an alignment error placing the lens or run into an open LED in the future. Other than that, use whatever you're comfortable with with gluing down the wayward lens and tacking down the lens' that haven't fallen off yet..

[hub...@ccanoemail.com]

On Wed, 12 Jul 2023 13:15:21 -0700 (PDT), "ohg...@gmail.com"
<ohg...@gmail.com> wrote:

OK Thanks again.
I'll probably be getting at it next week - fingers crossed.
John T.

[ohg...@gmail.com]

Be careful handling the display. Out of the frame, they are exceptionally fragile. Most first timers make almost the same mistake when laying the display back down in the plastic guides. Check, then double check the four corners and make sure the display is nestled *inside and below* the corner guides. If the display is sitting the tiniest bit up on one of the guides, the display will crack when you install the outer mask.

[hub...@ccanoemail.com]

On Fri, 14 Jul 2023 09:09:09 -0700 (PDT), "ohg...@gmail.com"
<ohg...@gmail.com> wrote:

Thanks !
One of the youtube videos that I watched ended with that very thing
- cracked display - he didn't elaborate on exactly how it happened
but it was in the re-assembly ..
John T.

[ohg...@gmail.com]

He probably didn't know what happened. Some TVs have a mm or more clearance on each of the 8 corner guides and the display settles in nicely between the plastic corner guides. Some TVs have less than a mm and it's easy to get the edge of one corner of the display sitting on top of the plastic guide - and it's not easy to see. Once the outer mask goes in it just nips the display and it cracks like a windshield. I always triple check the corners with my fingers to ensure the display is sitting below grade. Last week I had a Samsung where I could not get all four corners to sit down below grade at the same time - BTW, use a suction cup to gently move the display around. What happened was the metal pan chassis was racked a bit into a very slight parallelogram figure instead of a rectangle. I removed the display, picked up the chassis, flexed it a few times, and put it back down on the bench. This time the display went in. If it didn't, my next plan was to relieve some of the plastic guide with a Dremel to provide more clearance which I've done a dozen times or more on some TVs.

[hub...@ccanoemail.com]

On Tue, 18 Jul 2023 11:56:37 -0700 (PDT), "ohg...@gmail.com"
<ohg...@gmail.com> wrote:

I stumbled on this guy's video - and used his procedure -
which avoids the over-handling of the display -
he leaves the display on the table and lifts away the TV !
- have a watch and critique - I don't see a downside.

https://www.youtube.com/watch?v=WHMJCxDfm0k

His TV has 4 raised bolt-mounts that allowed him to simply
flip the TV over, once the back was removed, and the circuit boards
were not touching the table - my TV only had 2 of those - but
luckily - my wall-mount brackets provided 2 bolts that I used
for the other 2 points - as elevators ..

My dis-assembly went OK - a couple of sneaky screws holding
the back cover on ; and a little extra persuasion
was required on the corners - when un-clipping the TV body
from the display frame.
I had 2 lenses that had fallen off and found 2 more
that came off with just a slight wiggle.
I'm waiting for the silicone to set and then re-assembly.
John T.

[ohg...@gmail.com]

Some TVs (RCA Proscan) actually *require* the back pan to be lifted off the screen because the screen is bonded to the outer frame.

This guy got away with it this time (I assume, didn't watch the whole thing) but what can happen is that one corner of the screen can still be moved out of position from the frame guides because it's not bonded to it. If it slips a mm out of position, the display will crack when the pan is lowered into the frame. If you do it this way, what I would do first is to tape the screen to the outer mask before any disassembly with a good quality masking tape to try to avoid screen movement as much as possible.

His method does eliminate some screen stress (which isn't a problem if you're careful), but it's not worth the tradeoff to me because I can't see if the display is still nestled down between the plastic guides.

Hopefully, your reassembly will go well.

[hub...@ccanoemail.com]

On Wed, 19 Jul 2023 06:55:57 -0700 (PDT), "ohg...@gmail.com"
<ohg...@gmail.com> wrote:

Nope - cracked screen .. :-(
I think it happened just as you said - slight mis-alignment when
first re-installing the TV onto the screen + screen frame ...
I had to remove it and check things and re-installl .. but I'm
pretty sure that the damage was done.
Live & learn.
Thanks for your advice just the same.
John T.

[ohg...@gmail.com]

If it's any consolation, there's a high mortality rate on the first few most people do, and no, there's no coming back from any damage if the internal glass layer gets fractured. Even we pros crack one here or there.

The single biggest reason displays get cracked is that tiny misalignment between the display and the four corner guides. I not only inspect by eye through my opti-visors but run my fingers over with my eyes closed to feel that the screen is indeed below grade on the guides. That's why I do the top pull of the display on most units so I can be *sure* the display is nestled down and below grade before the outer mask goes back. Some (like RCA, Proscan, some Elements, etc.) bond the display to the plastic channel so it A) won't move and B) is easier to remove by pulling the back pan. LG doesn't bond the display to the guides so I do those by pulling the display from the outside/top.

Sorry it didn't work out.

[hub...@ccanoemail.com]

>
>Sorry it didn't work out.
>

I got the new Sony working - except for getting TV box remote
to work with it.
The new TV was quite-something - the initial setup involved a
series of " Terms and Conditions " from Master Google !
- inescapable, no option to opt out, sheeesh ..
It makes me afraid to use the TV's wifi !
John T.

[three_jeeps]

This insight/information is invaluable - I wish I knew this when I tried to repair my 55" Samsung. Wrestling a 55" panel back into the frame is quite a challenge.

[three_jeeps]

The LG TV replacement I got for my Samsung had a similar terms and conditions section...actually, a number of them. It makes for interesting (and long) reading. For the LG, one basically gives LG the OK to do anything they want in terms of monitoring and harvesting data from your TV. IIRC, I was able to decline everything. Not sure how I'll handle sw updates. Probably on a usb stick. I was also able to turn off the WIFI. The only thing I have plugged into my tv is the Amazon firestick which I am sure they use to see what I watch on Netflix, but at least they arn't watching everything on my TV. A few years ago LG got slapped with some big fines for not disclosing what all they were harvesting from the TV so I'd like to think they cleaned up their act.

The whole TV connected to the net issue is bass-ackwards. The mfg position is that the TV will be plugged into the net (one way or another) and all the interfaces go through the manufactures software. Instead, it should be that the unit is not configured for the net and the user can choose to enable it initially, or disable it whenever they want.
j