Samsung 46 Smart TV-Bad T-Con again?

[BluDuk]

Replaced the T-Con board on my 2-1/2 yr old Samsung UN46D6420UFXZA after screen went black. Installed the new T-Con and after 3 days, started seeing scan lines, ghost images, double images. Today, got black screen with horizontal lines at bottom. Recycled power and got more lines halfway up screen which then faded to black. Recycled power again and got full picture but picture is grainy. Thought my LED screen was bad but these symptoms make me think I got a bad replacement T-Con board. Can anyone help. Paid $1600 for this TV and really don't want to scrap it if it's just the T-Con board again. Could something else be cause the T-Con boards to fail? Pics of what I was seeing below.

[tom66]

Re: Samsung 46 Smart TV-Bad T-Con again?

That looks like a bad LCD panel to me, not repairable unfortuntely. I've seen tons of these with the same fault popping up on eBay, terribly unreliable.

[BluDuk]

Re: Samsung 46 Smart TV-Bad T-Con again?

Wow, not the news I was hoping to hear.

Is there anything I can do to definitively point to a bad LCD panel vs some other component failure?

I read another post about jumpers JP852 or JP854 being incorrectly installed on Samsung power supplies causing flickering. The fix was to cut the jumper. My power supply BN44-00427B actually has both of these jumpers. Could something like this be the cause of what I'm seeing?

Based on other poster's luck with Samsung service of not replacing failed panels on young TV sets, seems like this unit will be destined to be cannibalized for parts on Ebay.

[BluDuk]

Re: Samsung 46 Smart TV-Bad T-Con again?

A couple follow up questions:

If this is a bad LCD panel issue, does that mean that the tab connectors are failing?

This is a pretty thin panel, once I remove the edge trim, how do I get to the tab connectors to check them?

There appears to be black tape around the edge of the panel? Does removing this give me access to the tab connectors, or is there more I need to disassemble?

[tom66]

Re: Samsung 46 Smart TV-Bad T-Con again?

Tab bonds could be the cause though I've seen people with this fault having no luck with tabs. You would have to remove the frame very carefully to get to the tabs - there will probably only be ones at the top of the panel.

JP852/854 are re: backlight on older Samsung TVs (B- and C-series, I believe), not relevant to your set. Anyway, they don't affect image, just backlight. And they weren't incorrectly installed - cutting them is a bodge which fixes a fault with the AC-detection circuit which is what causes the backlight to flicker.

[BluDuk]

Re: Samsung 46 Smart TV-Bad T-Con again?

Thanks for the insight. What is the best way to dispose of an LCD panel once I've cannabilized boards to sell on ebay?

[tibimakai]

Re: Samsung 46 Smart TV-Bad T-Con again?

Which model is it? It is good to know. I know that the D series is horrible with panels. C series with mainboards.

[BluDuk]

Re: Samsung 46 Smart TV-Bad T-Con again?

My TV model is a UN46D6420UFXZA. The panel model is shown in the attached pic.

I did spend a fair amount of time cleaning and checking connections and tab bonds. Didn't have any success eliminating a bad LCD panel vs a bad replacement T-Con board. I think I will try to exchange my T-Con board to eliminate that variable. I'm having a difficult time thinking my T-Con board and LCD Panel both failed at the same time.

Exchanging the T-Con board only costs me shipping and if I'm lucky it will fix it. If it is the LCD panel, I'm no worse than I am now and I'll have to go look for a new unit before my wife comes back from Europe.

[tom66]

Re: Samsung 46 Smart TV-Bad T-Con again?

If only Panasonic still made plasmas.

There are essentially no good reliable TVs left (unless you spend big bucks on expensive Samsung plasma - F8500 etc..) LED-LCD is too unreliable now. Failure rate is abysmally high for new TVs.

And AMOLED will make them even more unreliable :/.

[tibimakai]

Re: Samsung 46 Smart TV-Bad T-Con again?

I have picked up one of these and it was a bad panel. D series seems to have a lot of issues with bad panels.

[Theprince]

Re: Samsung 46 Smart TV-Bad T-Con again?

Where you able to confirm that this was the panel and not the board?

[tom66]

Re: Samsung 46 Smart TV-Bad T-Con again?

The consensus is on this forum TVs showing that symptom or other similar symptoms have a failed panel.

[Theprince]

Re: Samsung 46 Smart TV-Bad T-Con again?

sad news. Thanks for the response. The fourth image from the post above is the most accurate depiction of my issue, although it gets worse with extended viewing time and will even begin to flicker (not certain if the flicker is related or not.) So does that mean that my best bet is still to replace the whole thing or are there reasonable self-repair options?

[tibimakai]

Re: Samsung 46 Smart TV-Bad T-Con again?

Where you able to confirm that this was the panel and not the board?

Mine had different issue, half panel shorted. If I removed one ribbon from the panel, the other half would work nicely.

[Theprince]

Re: Samsung 46 Smart TV-Bad T-Con again?

Interesting addition: I've discovered that the picture is significantly better if I view in 3d mode (2d->3d conversion mode specifically) the lines are still present but fine and the image isn't blurry nor does it flicker. I saw this video http://www.youtube.com/watch?v=i-jQZ-TQdgU suggesting that I cut jumper jp854 to stop the flickering can anyone confirm this works for the UN46d6420? If not I'll have to post my results next week. Thoughts?

[DemonBG]

Re: Samsung 46 Smart TV-Bad T-Con again?

Based on the last statement i would think it MAY be anothr T-con issue... if it was the panel it should make no difference if it was in 2D or 3D mode...

If you have the option of replacing the T-con again for free - I would give it a go.

Good luck,
Demon

[tom66]

Re: Samsung 46 Smart TV-Bad T-Con again?

Interesting addition: I've discovered that the picture is significantly better if I view in 3d mode (2d->3d conversion mode specifically) the lines are still present but fine and the image isn't blurry nor does it flicker. I saw this video http://www.youtube.com/watch?v=i-jQZ-TQdgU suggesting that I cut jumper jp854 to stop the flickering can anyone confirm this works for the UN46d6420? If not I'll have to post my results next week. Thoughts?

That applies to backlight flickering only on CCFL backlit LCD panels. Not applicable to your set.

In 3D mode the panel is driven at a higher frequency, maybe this hides some kind of issue that only appears on the lower drive frequencies.

[JD2019]

Re: Samsung 46 Smart TV-Bad T-Con again?

My TV is doing the exact same thing. Any luck? I did test the connect to the tv, and I was getting about half the voltage on pin 2 and 4.

[nomoresonys]

Re: Samsung 46 Smart TV-Bad T-Con again?

My TV is doing the exact same thing. Any luck? I did test the connect to the tv, and I was getting about half the voltage on pin 2 and 4.

Several symptoms in this thread, what exactly is your tv doing?