Another Sony with Tab bond failure. KDL-46S4100.

[lookimback]

I have lost count as to just how many of these I've encountered. This is the third this week though. I had a KDL 52W4100 the other day. I'm kicking myself over that one because it wasn't that bad and I think I could have fixed it. But, i didn't even waste my time trying. I wouldn't have sold it, but would have kept it for myself. Anyway, I'm wondering, has tried using an iron to heat and press the tab back in place? Would that possibly work? I know about the shim method, it's just too unreliable for me.

[tom66]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I've tried hot air - to no avail unfortunately...

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I kind of figured that. I know the tape (can't remember what it's called) only has a shelf life of a couple months.

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

Someday, when I get a big enough shop, I'm going to try to make a jig which could be used to align and fasten the tabs with new tape. I know how crucial the alignment is, and that the manufacturers have multi-million dollar machines for this, but that doesn't mean their way is the only way. I think I could make a jig for a few hundred bucks which would work.

[splitcrete]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I tried running the set covered with towels to over heat the bonds. That failed....

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I think the idea would be to heat them, while at the same time, pressing them in place. And then, I'd say the pressure would need to be maintained until it cooled.

[splitcrete]

Re: Another Sony with Tab bond failure. KDL-46S4100.

Then do we still want to use thermal pads to hold them in place, to keep them in place ?

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

It seems to have not worked. I don't think it's the adhesion of the tab to the panel or buffer board. I think it's the adhesion of the chip on the tab, or in some way, the tab itself. I just found the exact same panel in my basement and can't remember why I put it down there in one piece. I usually strip them completely. I think maybe I was unable to test it or something. Maybe I'll get lucky.

[tom66]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I think it's the chip bonding too. I've noticed stronger benefit when pressing on the chip directly. In my opinion the tab bond "repair" is anything but - it will simply prolong the time until permanent failure. Maybe if caught early it'll be easier to fix.

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

That panel I found in my basement turned out to be cracked. No luck for me today. I removed the bad tab and the ends of the chip are not adhered to the tab so I'd say that is the problem.

[ReeceyBurger123]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I have only ever been able to fix one lcd screen with tab bond issue with foam tape by sticking it to the tab then reinstalling the frame but if the set got knocked the lines would reappear, and it was a 50" so obtaining a replacement screen was almost impossible, its a pain.

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I don't even waste my time anymore, but this one just got me curious.

[Shinju]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I don't mess with any LCD/LED Sony panels anymore if they have screen issues I just gut the good stuff and toss em in the e-recycle bin and be done.

[lookimback]

Re: Another Sony with Tab bond failure. KDL-46S4100.

For a while, I wouldn't even buy Sonys. Aside from the notorious tab failures, they also have the parts which have the same part numbers, but are not the same part. Meaning, you need to order by serial number. That can be a nightmare for a buyer, and a seller.

[Shinju]

Re: Another Sony with Tab bond failure. KDL-46S4100.

Yes, that's the case for a lot of the older LCD units, newer ones like 2009 and up seem to share a lot of parts.

Mostly I pass on them too, although I did take a chance on a newer 2011 LCD no separate t-con (Built into the panel) had red screen and ghosting like a gamma chip. I even think I saw it on the TFT board, Funny it only had 2 tabs one left and one for right going from the screen to the board and there was not any IC drivers on them either they were built on the board or fused into the LCD panel someplace.

Probably could have been saved but I said NEWP and gutted it.

[tom66]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I fixed an older Sony. But only ever done one. Notoriously difficult to fix. Like Hitachi plasmas....

[Shinju]

Re: Another Sony with Tab bond failure. KDL-46S4100.

I fixed an older Sony. But only ever done one. Notoriously difficult to fix. Like Hitachi plasmas....

^ lol my only bane right now is a Hitachi Plasma!

[ReeceyBurger123]

Re: Another Sony with Tab bond failure. KDL-46S4100.

Talking of hitach plasmas got one coming on Saturday with vertical lines down the screen I will try reseating the ribbons on the y sus I will make a thread if not successful.
Here is a picture of it that the client sent.

[Shinju]

Re: Another Sony with Tab bond failure. KDL-46S4100.

In my personal experience with full screen lines like that, its always been a bad panel. Looks like an older Hitachi since its got side speakers.

[ReeceyBurger123]

Re: Another Sony with Tab bond failure. KDL-46S4100.

In my personal experience with full screen lines like that, its always been a bad panel. Looks like an older Hitachi since its got side speakers.

Thanks for the reply, I have seen before that loose connections on the ribbons can cause this but as you said it could be the screen.