LG 43UK6300PLB has backlight but no video

[edugimeno]

Hi! This TV was ready for the trash so I picked it up before it was thrown away

It's pretty new, so I thought I should give it a try. I plugged it in at home and I was expecting blown backlight as most of the TV's that get to me, but in this case it showed backlight with no video at all (no logo no menu no nothing).

TV seems internally responsive, drives stdby led red when OFF, responds to remote to turn on and off, but gets no image at all
Anything common on these sets to start with?

Thanks!

[edugimeno]

I just found a video (https://www.youtube.com/watch?v=dkZwrlaWC74) of a guy who fixes the exact same model with the exact same issue, by using the mask tape method.

I've seen this method in lots of videos recently and I actually used it to fix one TV 1yr ago, but now my question is:

Is there a more "scientific" or accurate way to know how many and which pins to mask (or cut) to fix the issue? I mean, there has to be a way to identify the function of those pins and check which of them are shorted in the tcon boards so you just go straight to those pins feeding the shorted lines, am I right? As the try&error way seems that it all depends on your luck making up sizes of tape and positions... Also if you mask more lines than needed the result is a degraded image quality as you lose some horizontal lines


Thanks!

[edugimeno]

Anyone? Thanks!!

[vinceroger69]

this thread maybe worth a read LG 43UK6470PLC - no image - Badcaps
hopefully lotas Diah maybe able to advise too

[maneatingmonkey]

If you want to be "scientific" you could compare resistance values for each clock and data line between the left and right panel boards. But the quickest way is to just binary search - i.e. tape off half the pins, then a quarter, then an eighth, etc.

[edugimeno]

this thread maybe worth a read LG 43UK6470PLC - no image - Badcaps
hopefully lotas Diah maybe able to advise too

Yes, I checked that post and it actually shows that each TV needs different tracks to be taped...So each one has to find out. I guess that different TV lines could get shorted.
The thing is that if you cover too many lines, more than needed, you get flickering lines or a very degraded image with missing lines in between working lines.
That's why I wanted to hear if anyone know a way to find out which ones are bad.
Yes, like Maneatingmonkey mentioned above, having a dual side panel fed by two flexes, I could compare one by one from working to non working and see the difference.
I will be back with updates when I can put my hands on this TV

Thanks!

[edugimeno]

(Edited, wrong post...), its not letting me DELETE the comment

[edugimeno]

Last update, I spent some time last weekend on this TV and found a position where the tape would allow the TV to turn on. BUT there was a small (like 4cm) bar at the bottom where the image was a little degraded, like greyed out. I moved the tape patch everywhere right and left, tried shorted pieces of tape, and nothing, I had to give up and leave it as is, this is a summer house where I spend only a couple months a year so I will probably be able to live with this.

Thanks everyone