All Over White Washed Out Picture LG 42LF2510

[dicky96]

Re: All Over White Washed Out Picture LG 42LF2510

I re-seated the Tcon cables and the weird ghosting and darker area went away.

Interesting a bad connection on a Tcon cable could cause such a weird effect on screen

So I still have the very fine vertical lines. There is cyan one which sometimes goes black if you push gently against the right T-con cable and sometimes will disappear all together

There is a yellow one very close to the cyan one which does not want to go away.

I tried swapping the two Tcon cables but it makes no difference to the location or intermittent nature of the lines.

Do I have another faulty panel? This is so annoying after I fixed the AS15 fault, I could get the intermittent blue/black line before the repair but as it would go away with a touch on the Tcon cable I thought it was a bad connection and that seems to be the case.

The yellow line was probably there all the time but I could not see it due to the original fault

Anything else I can do with this?

Rich

[dicky96]

Re: All Over White Washed Out Picture LG 42LF2510

I got a little bit further too. By wedging a bit of folded over heat shrink down here (see pic) I can get the intermittent line to go away (or I can get more lines in the same narrow area of the screen depending where I stick it) So far I can't get rid of the one yellow line.

Can I get this piece of metal off (marked with an X) to get to the narrow PCBs behind it? The metal frame goes all the way round the screen panel I think. I have not tried to dismantle one of these things before.

What is the basic technique? Do I support the rear of the backlight metalwork on some wooden blocks or something so I can have the PCBs still plugged in to the panel and running, with the glass side upwards on my bench and then remove this metal framework to get to where I need to be?

At least the bench is wide/deep enough for the panel to fit on face down.

Rich

[attainteddragon]

Re: All Over White Washed Out Picture LG 42LF2510

unscrew the bezel, roll the set over so the panel is pointing up.
remove bezel and roll over to one side. should get away without disconnecting the speakers and buttons.
you will now have access to the metal securing panel. normally one piece that surrounds the whole panel.
there will be about a dozen screws that secure the outer metal frame to the back panel.
remove them, then you are ready to remove the outer frame.
i lift them from the opposite side from the t-con, just to prevent any pressure on the pcb and ribbons.
once removed you can power the set up and by pressing on the cof chips or the adhesion points where the panel joins the ribbons to locate the exact spot that the panel is having issues with.
applying some pressure with some thermal pads or rubber etc on the effected areas will hopefully remove the visual panel issue.
longevity of doing this can be from hours to years. there is no real permanent fix.

welcome to the world of lcd panels.

[budm]

Re: All Over White Washed Out Picture LG 42LF2510

https://www.badcaps.net/forum/showth...ht=tab+bonding
4 years and still running, same for these:
https://www.badcaps.net/forum/showth...ht=tab+bonding
https://www.badcaps.net/forum/showth...ht=tab+bonding

[dicky96]

Re: All Over White Washed Out Picture LG 42LF2510

Thanks guys,

I spoke with the owner and he is going to have a look first as there is just a one pixel wide pale yellow line on the screen. He is happy to pay for work undertaken as he accepts I did repair the fault he brought it in with.

I explained there would be an additional charge for looking at the Tab Bonds and that attempting to repair may fix it but could also make it worse or even destroy the screen.

Will see what he says, don't think I can say fairer than that

Rich

[dicky96]

Re: All Over White Washed Out Picture LG 42LF2510

I got all the frame off fine - thanks to the instructions it was easy enough.

There are two tab bonds causing problems.

One of them if I wedge a shim made from a piece of folded over heatshrink behind the ribbon to put a little tension on it then this gets rid of the line.

The other one has a few vertical lines on the screen close together but no matter where I seem to press it will not clear them all. At some points of pressure some will disappear and others will appear.

The problem seems to be around the little chip thing built into the middle of the ribbon. I can make it worse by running my finger along this area with a little bit of pressure and get a wider black line as they all merge together on the screen. Is there some technique to this? I've not tried this process before.

Rich

[attainteddragon]

Re: All Over White Washed Out Picture LG 42LF2510

the pressure required varies on every set. whether it is from above, below or near to remove direct pressure. i have had many that i have had to give up on.

[vinceroger69]

Re: All Over White Washed Out Picture LG 42LF2510

The chip on flex seems too be failing a lot were seeing more and more people mention them.

[Davi.p]

Re: All Over White Washed Out Picture LG 42LF2510

Those as15 have to be changed at the fly whithout to reason..