samsung 32 UE32D400

[tom66]

Re: samsung 32 UE32D400

That waveform confirms main board is sending video data, so my thinking is something on that bonded t-con board is bad, meaning the panel is bad. You might be able to find some way of harvesting the t-con from a scrap screen, perhaps via very careful re-bonding of that single tab (since there's only one to line up, it's marginally easier.)

[adamp91gvm]

Re: samsung 32 UE32D400

How are they stuck down

[tom66]

Re: samsung 32 UE32D400

Soldered I believe; you could try solder paste, but you'd need a precise stencil or a lot of patience . One other possibility is anisotropically conductive tape - it's tape which conducts only in one direction, allowing you to attach a ribbon with a piece of tape. 3M has -Z-Axis tape which is suitable for this application. However, as far as I know, no one has succeeded in doing this, yet.

You could be the first

[adamp91gvm]

Re: samsung 32 UE32D400

Guttered about this tv it looks spanking new inside and out

[tom66]

Re: samsung 32 UE32D400

Well, that's modern LED TVs for you. Reliability is terrible.

[adamp91gvm]

Re: samsung 32 UE32D400

Yup I think I'll start on a 42 inch lg I have with no pic tomorrow put this under my bed and forget about it for a bit

[adamp91gvm]

Re: samsung 32 UE32D400

I'm not giving up in this lol I'm getting power to the left side as I look at it but from here I'm getting nothing from anywhere on this the 220 one

[tom66]

Re: samsung 32 UE32D400

That seems normal for that configuration, as one end is grounded. Possibly VGL generation circuit (negative.) It's often not abnormal to get significant voltage drops across components. Electronics would be awful simple if everything worked at V+ or 0V...

[adamp91gvm]

Re: samsung 32 UE32D400

Ha ha I know I just really want to get this going

[tom66]

Re: samsung 32 UE32D400

Yeah I've been seeing quite a few 32" 720p Samsung panels dying. I am interested in fixing one at some point, but I really need to have one in my hands, probing everything, to find the fault. Maybe there's some easy, obvious fault, but I'm not seeing it.

[adamp91gvm]

Re: samsung 32 UE32D400

I know it's going to be something stupid that's what's getting me

[adamp91gvm]

Re: samsung 32 UE32D400

Stupid question time this next to the fuse is getting 12v ish into it but nothing from the other side is it suppose to ?

[tom66]

Re: samsung 32 UE32D400

It is a TVS surge protector. It shunts higher voltage transients to ground. It's an odd device in that position, I'm guessing it might be useful for some of the more inventive power supplies that we're seeing in cheap TVs which are horribly unregulated and could damage a normal T-con over time. I suppose since it's such a cheap device it's just some insurance for Samsung.

One end is grounded so you will see nothing "out" of it. That is how it works.

[mmartell]

Re: samsung 32 UE32D400

Is it a diode ? Remove power and test it to see which way it should be conducting.

[mmartell]

Re: samsung 32 UE32D400

Oops nm tom is on it

[tom66]

Re: samsung 32 UE32D400

Note: mmartell is correct... it could be a diode too, for reverse polarity protection, but that's really odd, only a wiring harness error would cause that and it would still blow the fuse rendering the module "failed" to most manufacturers... A TVS is also a diode. Just with a low voltage breakdown designed in.

[adamp91gvm]

Re: samsung 32 UE32D400

If I just un clip the ribbon to it and move it slightly I get a bunch of lines on the screen like black and white

[tom66]

Re: samsung 32 UE32D400

Do you notice any change on VOFFE/VONE when doing this?
I think it is a fault on that t-con board, but no schematic and no datasheet for the parts, it's hard to narrow it down.

[adamp91gvm]

Re: samsung 32 UE32D400

Would samsung have the schematic diagrams if I ring them

[tom66]

Re: samsung 32 UE32D400

No... I've never found one for LCD T-con except one old 26" AUO panel which is pretty different to newer panel.