Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Where on the tcon board would the voltage be checked i have never checked that on one but im sure i can. Is it near the lvds cable input or general location to look. What should the voltages be and do i just ground to metal chassis or frame while checking i know some test points need to be grounded in certain spots.

[tom66]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

It varies with each T-con. You will see white lettering next to a gold test pad.

[hienton2]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

I still think of main board. But you said Tcon at bottom of panel. Then watch for windex issue That make board corrosived

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Ok here are the TCon readings

VON 23.4v
vOFF -13.7v

[MisterD]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Spray freeze spray directly on the tab bonds one at a time waiting 10 seconds on each before proceeding with the next, try pressing on them after using the freeze spray.

You can also try heating the tab bonds with a hair dryer and pressing on them while they are warm, sometimes they have to be heated or cooled before you will get any results.

[tom66]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Both VON and VOFF look fine to me. There is also usually AVDD (15~20V), but this is generated on the same supply as VON/VOFF so all three or none should be present.

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Well i dont know what direction to go now. You think its the lcd panel or could i have main board trouble.

[tom66]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

I'm thinking panel or t-con. Doubt it's the main.

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

My instinct tells me t-con , i just fixed an insignia 47 lcd with a tcon. It would play for 5 mins do some weird picture colors and go out but still have sound. I feel like this is doing the same thing as the picture just gets worse and worse if you play 30 minutes or so it almost gets a ghostly white all over the screen but images can still be seen. Then i read about the samsung panel failures and have been scared its that and debating paying much for a t-con. Do you think if it was panel it would be progressive failure like this or would it be failing right at turn on.

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Heres a picture of the same ln46b650 a guy is selling the tcon from on ebay. He claims the lcd panel is bad. This is what mine looks like just thought it might be a better picture where you can see it. Maybe i do have a bad panel or maybe he dont know what parts are good or not.

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

So i followed mister D's instructions above and went back and re-analyzed the tab bonds on my lcd screen edge. I sprayed with cold spray and heated with a hair dryer at each of the 16 spots. I pressed them and saw no changes what so ever in picture. But as usual as the picture warmed up it got worse. I flexed the screen and moved it a little at the tab bonds and get no kind of change in my picture. Anybody?

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Well I got the new T-con in the mail and popped it in and bam same darn lousy picture. I guess its not that cause it did the same exact thing in progression. Well the big question now is do i try a main board or call it a bad lcd display and sell my parts. Thanks matt

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Anybody , what do you think?

[tibimakai]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

There are some chips in the 16 ribbons, do they heat up a lot?
Do you have sound?

[DakotaKid]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

I had a similar problem with this same model and it was the mainboard. I popped in a replacement from a TV with a broken screen and it fixed the problem immediately. I also have one with tab bonding problem where the picture starts out half dark and with lines and in about 10 minutes it pops in clear and perfect, especially if i give it a slight twist.

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

I have good sound the chips in the 16 ribbon cables get hot. Dakota kid you have given me hope. i may try a mainboard. Are the chips supposed to heat up. i have twisted and flexed
and cant find a bad tab connection.

[tibimakai]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Ifthey way to hot, them maybe the driver ICs are damaged. Inspect them for burned marks.

[tom66]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

The ICs on these sets run much too hot which is why they fail so often...

[snake91876]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Anybody else think i should go for main board!

[fxdfireman]

Re: Samsung 46" lcd ln46b650 vertical lines and a gridlike pattern on right half

Did you try a main board? Did it fix it?