How to repair a Soniq L32V12A 32" HD LCD TV
Dave fixes this one in the nick of time, just before his mum was going to ask" where is my TV?!"
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Hi. In the previous video, we looked at uh, troubleshooting and attempting to repair this heer crap Sonic brand uh you know one hung low brand LCD uh TV and well we pretty much uh, ruled out uh, most of the power supply and your traditional uh failure points with the electrolitic capacitors. There was nothing wrong with those I measured rails and scoped it and uh, got it with the meter and everything looked fine but it seemed very intermittent now. A lot of people responded with lots of comments so thank you very much for that.

uh, tips and all sorts of things and as to be expected, everyone sort of had like a different opinion of what was wrong with this. Some said oh, it's beyond economical repair and well it certainly could be. But upon replaying the video I noticed something that I didn't notice before that I didn't notice at the time cuz I wasn't actually looking at it and and uh, a couple of people also uh noted it as well. they they saw it on the video and it was when I actually uh when I was playing around with the thing I touched the TV like this and it changed it.

the image actually vanished or or flick it or did something. So um, that indicates that there's some sort of physical. It was too much of a coincidence. Okay that I just like I was playing around with it and I was look going towards the back like this and uh, you know I just touched.

gently, touch the front of it and the image vanish. So really, that indicates that there's a physical uh component to this fault. It doesn't mean it's the only fault, but certainly a physical component. and it's most likely the main fault a physical component in terms of some sort of connection or something like that.

And that makes sense when you're talking about. One of the symptoms for this thing was that it got uh, it was getting audio. Audio was working fine, but we were getting no picture. That was one of the symptoms of of various uh things that were going wrong and very, you know, flickering in the display and stuff like that certainly could be a bad contact.

Now we ruled out the power supply of course. So the proc: the power supply is basically powering all of the processing uh, engine down here in the main board and through that through to the LCD panel up the top here. So uh, really? I'm going to rule out any connections to do with the power supply. all the power supply go into the processor board here.

so what's left? Well, the only thing left is this multi-wave ribbon cable here going from the processor board up to this board up here, which upon investigation is apparently called a ton board, a timing control board and that uh, basically uh, splits out or handles the timing and splitting of the signal going from the main processor board to power in the LCD display up here. I've seen ones where they, uh, this sort of stuff is embedded on the main top. There's a whole top board up here, but we basically got two big multi-way flat Flex ribbon cables going here. so I'm going to suspect that it's one of those ribbon cables.
First thing I'm going to do though is power this thing on, see if I can reproduce the fault uh, based on just physically tap in or you know, physically Flex in the display. or maybe I'll get in here with my poker and I'll have a poker around on the and insulated poker of course. uh, poke around with the flat Flex ribbon cables in there and see if anything happens. Let's give it a go.

Now the thing just powered up and uh, the I got the power up sound and everything like that. but I didn't uh I'll turn my LCD around here. but I didn't get uh anything on the display so let me start having to poke around. So like it like it seems to be like completely gone.

Now that's what I said at the end of the last video and uh, the back light's on and of course all the power supply stuff is still working but sort of give it a flex. No I think it's sort of permanently permanently gone now. So I don't like look at that. it was Ni.

it was nicer when it was intermittent. Now it's like completely failed so that's good and bad. Uh, um, in this case though, it's It's kind of bad from the aspect of me trying to play around with the thing. anyway.

What I'll do now is I'll reat these uh flat Flex connectors cuz these can be a pain in the ass. Uh, these flat Flex connectors. So I'll resat those and uh, turn the power off first, reat them, and then, uh, try it again. So yeah, these can actually be a real problem.

So what you do is you just lift up the connector on these. Some of these work, uh, differently to others, but this one is designed to pop out like that. and these moldy way ribbons. they can be quite Troublesome The the actual ribbon itself.

Like these things inside never break, um, virtually never do so. But the connectors can be a bit Dicky especially if they'll put in, uh with somebody not using the right tongue angle. Um, so anyway, let me, uh, let me resat that sucker and is it in? Ah, sorry, my fingers are in the way here. You won't be able to see anything, but let's push that back in and resat that sucker there and I'll just repair it step by step.

So I'll know if it comes good now. I'll know which one it actually is. Saw the backlight. come on there.

but no, no boot image there we go. So it wasn't that connector actually. Just as it. a little aside, this Is a good example of capacitor dialectric absorption.

Now what I've done is I've uh, disconnected the TV Okay, so that main uh, capacitor as I explained in the last video is uh, still retaining a ton of charge. Okay, there's no bleed resistor across that, so that's still going to have a couple of hundred volts on it. Easy and it'll take. you know it could take tens of minutes for that to actually.

Decay Now, as I said, could use a Multimeter with the Uh low low impedance uh voltage measurement usually designed for eliminating ghost voltages and stuff like that. but you can use it for safely discharging a capacitor like this because it's low impedance. So we'll get in there and you'll probably see the voltage shoot up quite quickly. It might even overload.
and then, yeah, overload. 40 volts, boom and then drop down to0 volts. now. look I'm holding the probes on there.

Okay, so this capacitor is now you would think discharged. look 0.1 Vols Okay, but due to the phenomenon of dialectric absorption Capa There we go. it's discharged to zero. Okay, to within 0.1 volts there.

All right. So what we'll do now? it's like a minute later I'll switch it over to volts. DC Okay, so we have the high impedance input instead of the low like 10 Meg input impedance instead of the low input impedance of a couple of K uh, which we discharg that capacitor with. We saw it discharg to zero.

But watch this. I mean this is a significant time later. Look at this. it's recovered to 2.9 Vol And increasing that is dialectric absorption.

Okay, we'll do it again. Here we go there we go: I Just charge the thing up. We'll change it to low impedance mode. We'll do this.

Boom. There we go. It's discharging and we'll do it straight away now. Okay, okay, it's completely discharged.

Look at that. Let's make sure it goes down to 0.0 Come on. Ah, near enough. Good enough for Australia Here we go and look at that voltage creeping back up.

That's dialectric absorption. the phenomenon of a capacitor to recover from its charge after it's been discharged. And I'll leave that to you to go. Google and have a research on dric absorption cuz it is quite a uh, interesting subject so well worth looking at.

now. this connector up the top here. I've taken that out. It's a different type.

It's physically got a connector uh, mounted on the end of the flat. Flex Like that it's got some shielding tape over that. so I'll just reat that back in and see if that makes a difference. And I'll also just might as well just reset these suckers as well.

But hey, I'll do it step by step. No still no boot image. bummer. Next up, we got the top side connector.

Absolutely tiny and these things are re even more of a pain in the ass than one down on the processor board. So I mean you know there's not much that can go wrong on this uh ton board here. Really? I mean there's a couple of passive bypasses. Oh does I don't know? Hang on.

Sorry about the shaky image here. I can't uh, get my macro lens on my tripod. Does that look like like a fuse? H Well I've taken this little ton board out here. It was stuck on with a double-sided tape held into a little plastic Uh holder on there and uh, it's an LG display.

so presumably it's an LG panel in here. So LG Display TL Uh, 236 ml. Couldn't get any Uh data on that off the bat. but uh, anyway, it is.
there you go. LG Display Co Limited and Uh designed in 2009. Probably reused in a whole bunch of different Uh panels, no doubt. So um, this takes the Uh differential.

Here we go. takes the differential pair Lvds signals coming in. there you go and uh basically Uh does timing and control stuff and has differential pairs coming out that go to the main Uh panel and dries the panel. But look at this.

look at. this is look what we have here. We have ourselves When you have when you see a u a flat Flex cable like this and you got multiple pins in parallel like we do here, they're that's obviously the power input pin cuz they need you know, a fair bit of power. These flat flexs and these connectors, um, don't have much current capacity per pin and per wire so often it's very common to parallel them up like that.

In this case, we've got four passing through a cup. not one, but two. Z oh, resistors there and they go into what looks like there you go, a poly switch or fuse. that uh, then goes through to the bypass caps on here.

So let's measure that sucker and uh, see what we get? because I tried playing around with the connector up here and that didn't fix the issue. So H So let's measure that puppy and hello I'm making contact there. that's my probe shorted out. hello I Think we have a fail that is open and that sucker ain't going to work.

That's why we're now getting no pitcher at all and no amount of proding and poking and shaking and um, trying to coers this thing into working. We'll get that to work, but got ourselves a blown fuse or poly switch on the board there. Yeah, I'm not sure. uh, off hand.

TC Um, not sure of the code there, but jeez, yep, that ain't going to work. We need to fix that now. I'm not sure of the exact brand of that, but I did find a reference to TK in a little fuse data sheet and it is actually fuse, not a poly fuse or a poly switch like a resetable uh fuse I think it is just a fuse. that's why it's blowing like that.

I'm not sure why it would have blown whether or not it was, you know, just a dodgy uh part that was going into Mitt and failed I don't know or the intermittency could have to do with the fact that it was something to do with with the flat Flex connections and then I don't know. some surge current eventually took it out H I you know I don't know. but anyway, that um, that marking is for according to little fuse uh 1 and2 amps so don't have one of those to hand. but I can probably bodge something in there that's for sure.

or hey, just to get up and run in. Eh, short it out out. Well the best I had to hand was a axial fuse like this. so I just bodged that in there.

Eh, that'll get us up and running all right. Let's give it a B again and plug it in. I've reconnected the board up and uh let's give it a go. Hello McFly there we go.

Hey there we go. look look Well not surprising because that thing did uh did blow so of why it actually did that but look at that. there we go, we've got our image back. sorry I can't uh get the camera on a good angle? Okay let's uh have a poke around here and uh, I'll turn the L LCD around so I can actually see it.
It's good to have a mirror or something like that for this sort of thing because you don't want to go sort of sticking your head around the front like this with your tongue at the right angle, trying to poke at the back. Eh, not that great as I said insulated poker. But uh, uh. All right.

hey, look at that. I'm touching that ribbon cable at the top. That's the one on the bottom of the ton connector. Okay, that's the top of the ton connector.

This is the ribbon cable down on the processor board. There you go. so it is. Look at that son of a gun.

I'll hold that in I'll physically hold that in, hold it and release t Look at that. It is an intermittent connector. That one with the actual connector on it. It's not the one.

It's not the actual flat Flex one. It's the one with the Um with the physical sort of, you know, semi latching connector on there. But I think I think we've solved our issue. I'm not sure why that fuse went.

uh, no idea. Um, I'm not going to fuss over that at this stage. Uh, we got ourselves a win. So there you go.

It does look like that one is the culprit. and yeah, I was like poking that connector down and down in there like that. and I can actually see a reflection off the back wall of that thing actually going off and on. So there you go.

Just physically poking that a bit can cause that, of course. Um, you'll get thermal issues with this as well as the as the thing heats up. you know, a slight expansion in, uh, stuff and so that can, uh, cause an issue both mechanically as part of the thing and also perhaps thermally. So um, because you're going to get that heat rise of course from the Uh from the big Power Supply right down under here.

So there you go. That was the issue. Um, well, I'm going to say it is anyway. um, um, I'm going to call that one uh, done and dusted.

I'm going to have a bit more, uh, play around with it. um, to sort of, you know. uh, see exactly I Don't think it's a Reflow issue I don't think it's a solder joint on there I did look at this under the uh mantis microscope and it looked pretty good. So I'm not going to like Reflow that board or anything like that.

it's not. Uh, it's not worth it I don't think. but uh yeah. I'm going to certainly have a bit more play around with this uh with this connector here.

got to be careful cuz it is right next to the Uh power supply here so you know, um, best to dick around with that with the power off if you're physically going to get your little uh fingers in there and have a play, but there you go. I'm going to call that one found and potentially fixed. Awesome! and I've had a bit more trouble with this thing. so I've just sprayed some uh contact cleaner up into there and the contacts as well I Don't trust this bloody connector.
It's a man just looks and feels dodgy. Don't like it? It doesn't lock into place properly and not now I've actually found the thing is more reliable once. I've actually got it out and free hanging like that. So maybe I'm I should really get in there, tape up, you know, bog up that connector or something like that and maybe refeed it back I could even put like a Myar sheet over the Uh power supply, some sort of insulating Ma sheet over the Uh power supply and just I don't leave it free hanging I guess um, you know once I do up that connector and everything.

can't see why I couldn't uh, do that. but or maybe even feed it back under once. I've um, really fixed up this connector and you know, taped it up, maybe bogged it up properly? I don't know, but yeah, it's seems to be going okay. okay now with it free hanging, so it's definitely the issue.

Now there's one viewer who did, actually, uh, suggest that a common issue with these things is, as the Um backlight ages, it starts to interfere with the Lvds lines. and one way to solve it is to, uh, put shielding tape like all over the thing, like completely cover the thing to isolate it. I I Don't know I don't necessarily buy into that one. Um, but uh yeah, I mean we're because we were getting like physical, uh, pokeing.

You know, I could physically make it come and go like that and well, yeah, proximity. Not a huge deal. but anyway, um, yeah, this thing is essentially, uh, fixed back up and running works very reliably now. I've really, uh, taped up, you know, I've put tape on there to really physically hold the connector in uh, place and it seems to work really well now.

TDA that's a win. It's back together together and I'm all happy. and uh, I've you know, banged it around, done all sorts of, uh, weird and wonderful stuff and uh, it seems fine I don't have the uh, um, Raspberry Pi plugged in anymore, but uh, there you go menu. Everything's fine.

bang bang bang boop boop boop. oh that was just that wasn't me. that was just, uh, the Timeout on the menu so everything's fine. Looks like we had at least a dodgy, uh, flat.

Flex so one of those flat Flex interconnect connectors in there, real pain in the butt on that ton board and that blowing fuse. I'm not exactly sure why the fuse blew, but replaced it with the same Uh rating one and everything's honky Dory That's a win. Catch you next time.

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By YTB

27 thoughts on “Eevblog #631 – how to: soniq lcd tv repair part 2”
  1. Avataaar/Circle Created with python_avatars Light Science says:

    How did you know that was a fuse and not a capacitor

  2. Avataaar/Circle Created with python_avatars Mark Adolphus says:

    Btw .. if you get it working will we see u pop on there and sell some cleaning product?

  3. Avataaar/Circle Created with python_avatars Mark Adolphus says:

    @4.30… Chinese wire….. I hope you find the fault the fix got the same TV same issue exactly… Gone are the days of the days of turning off the lights to see where the dust accumulation is causing an arc them just vacuuming it all out

  4. Avataaar/Circle Created with python_avatars Stavo Piqqoet says:

    If I had not seen this video I was ready to buy a new monitor/TV …. fuse was fine … flat composite cable with the connector you detected as dodgy …. Screen returned TA DAA !! thanks for your help 🙂

  5. Avataaar/Circle Created with python_avatars Peter H says:

    Ummm…the fuse was probably blown because you shorted out a component inadvertently with your test probes.

  6. Avataaar/Circle Created with python_avatars David Ujcic says:

    I love the hedgehog TVs.

  7. Avataaar/Circle Created with python_avatars Jason Pell says:

    You sir are a tv saver! Exact same issue with me a loose ribbon cable, reseat and tv is working. In my case I had no issue with the fuse! Thank you so much for this video. As a fellow Aussie love watching your videos, I'm only the most basic of electronics dabbler so much of what you say is over my head, this though I could fix which was nice. No need to replace my shed tv now

  8. Avataaar/Circle Created with python_avatars Mark dj Deenix says:

    Hi Dave I’m watching your video a lot and I find you content really interesting 😎👍👍I do repair on pioneer mixing equipment and have found that sometimes a layer of sellotape on the blue side of the ribbon cable helps.the socket bows /warps due to heat and the tape make up the difference

  9. Avataaar/Circle Created with python_avatars Robert Gennari says:

    Looks as though my previous comments were right….bad connection!

  10. Avataaar/Circle Created with python_avatars muhammed sons says:

    Dave you are a crazy man

  11. Avataaar/Circle Created with python_avatars Ajay Kumar Targotra says:

    hi deve, i am looking for soniq e40w13a bios program,,any suggestion.

  12. Avataaar/Circle Created with python_avatars jlucasound says:

    Great job, as always! I learned more from you in this two part than I have with years of reading books that give mathematical equations. Hands on works for me. I can SEE it. Thanks, Dave! G'Day Mate!!

  13. Avataaar/Circle Created with python_avatars TmS x Snxgged says:

    This dude sounds like Rackaracka😂😂😂

  14. Avataaar/Circle Created with python_avatars Răzvan burada says:

    Hello can someone help me? I have an LG 50LB650V with vertical lins on the display I tried changing the TICON board but it didn’t help !

  15. Avataaar/Circle Created with python_avatars ja go says:

    Your comment was good enough for Australia. That's acceptable. If you said good enough for China I'd be seriously concerned

  16. Avataaar/Circle Created with python_avatars Chris Wyatt says:

    When the tv is turned on it just has red screen,blue screen,green screen,white screen then goes black?

  17. Avataaar/Circle Created with python_avatars Robin Sattahip says:

    Throw that piece of junk away and buy mom a good TV.

  18. Avataaar/Circle Created with python_avatars Robin Sattahip says:

    Never let an engineer do a technician's job. (smile)

  19. Avataaar/Circle Created with python_avatars Muhammed Haji osman says:

    I have already toch the power supply it did not kill me it was a little shock

  20. Avataaar/Circle Created with python_avatars Greg Winfield says:

    thanks Dave. It seems my in laws Soniq had the same issue. I ordered a replacement fuse and soldered it in, currently typing this via my Mac in large screen format 😀

  21. Avataaar/Circle Created with python_avatars Greg Winfield says:

    i've been given one of these identical things with the same identical symptoms Dave. will give it a crack. thanks for your insights and methods on how to work thru it. i'd made the same conclusion of power but, perhaps not 🙂

  22. Avataaar/Circle Created with python_avatars soosai steven says:

    I was in the assumption Samsung makes the worst TVs in the planet but this shit looks creepier.. what's that, plastic structural support?

  23. Avataaar/Circle Created with python_avatars TheJavaSync says:

    some another case, harder than that (flickering, double image, slow motion .. etc) , make videos of them Dave, pls 🙂

  24. Avataaar/Circle Created with python_avatars steven whitney says:

    gday i have a soniq 40" led lcd e40s12a-au and it has a horizontal line accross the top of the screen about 3-1/2 inch wide and not completley solid but coloured lines, I believe its t con board but not sure how easy to fix or replace
    thanks steve

  25. Avataaar/Circle Created with python_avatars lez briddon says:

    Isnt this a vestel chassis, that warped wobbly bezel just shouts vestel to me

  26. Avataaar/Circle Created with python_avatars FerretAD says:

    Dave, I understand some uses for 0 Ohm resistors, but cannot figure out why there are 2 of them just after that blown fuse?? Why did they put the resistors there, as opposed to just continuing on the tracks? Thanks.

  27. Avataaar/Circle Created with python_avatars ThatOwensBloke says:

    genius. i have the same telly, same symptoms (never got to the no screen stage, fuse was still ok). i rerouted the ribbon over the power supply and all tested ok.
    thanks heaps for the great troubleshooting performed in these videos – great to watch the way you nutted it all out. Tim.

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