samsung UN46D6050 sound but no picture

[rlega]

Re: samsung UN46D6050 sound but no picture

Hello everyone,

I have tried everything I can and TV model UN46D6050TXFZA is really getting on my nerves. Like I have mentioned before, I purchased that TV and there was sound, but no picture. Luckily I purchased a broken screen TV that came with the same mainboard and t-con, the only different part was the power supply. I changed mainboard and t-con, nothing, I used one and one, nothing. I purchased a power supply online, and nothing. The smart logo is not visible, never visible, there is sound, but no picture. When you change channels, you can see the lights on the back of the screen change, and the sounds comes back again pertaining to the channel, but no picture.

I have changed all the electronics parts, mainboard, power supply board and t-con with no luck.

I remember I fix a 32" TV, thread here by following member Wizard steps. I found the diode online, replaced it and the TV worked.

Perhaps TV UN46D6050TFXZA has a diode somewhere that its not working?

Someone with more knowledge than me, perhaps can gimme a hand.

Thanks a lot

[tom66]

Re: samsung UN46D6050 sound but no picture

If you have swapped all the parts over and it still does not work, it really only leaves one possibility and that is that the LCD panel is bad. These newer D-series Samsungs are really bad for reliability of the LCDs so it's a distinct possibility. Maybe it's worth changing over the cables, too, just in case.

One test you can try is to go to the T-con board and unplug one of the two ribbons connecting it to the screen. See if you get half a picture. Repeat for the other side. If one side shows half a picture it means the other is shorted, i.e. bad LCD panel sorry it can't be fixed.

[rlega]

Re: samsung UN46D6050 sound but no picture

If you have swapped all the parts over and it still does not work, it really only leaves one possibility and that is that the LCD panel is bad. These newer D-series Samsungs are really bad for reliability of the LCDs so it's a distinct possibility. Maybe it's worth changing over the cables, too, just in case.

One test you can try is to go to the T-con board and unplug one of the two ribbons connecting it to the screen. See if you get half a picture. Repeat for the other side. If one side shows half a picture it means the other is shorted, i.e. bad LCD panel sorry it can't be fixed.

Hello tom66,

Thanks for the reply.

I forgot to mention that I have used the cables from the broken screen TV I purchased, and still nothing. I even changed the 2 flex cables from the t-con to the lcd panel.

Anyway to test the LCD panel?

Thanks

[AFajitas]

Re: samsung UN46D6050 sound but no picture

Did you shine a flashlight into the screen to make sure it's not the back lights or inverter?

[tibimakai]

Re: samsung UN46D6050 sound but no picture

Tom, told you what to do:
"One test you can try is to go to the T-con board and unplug one of the two ribbons connecting it to the screen. See if you get half a picture. Repeat for the other side. If one side shows half a picture it means the other is shorted, i.e. bad LCD panel sorry it can't be fixed."

[rlega]

Re: samsung UN46D6050 sound but no picture

Tom, told you what to do:
"One test you can try is to go to the T-con board and unplug one of the two ribbons connecting it to the screen. See if you get half a picture. Repeat for the other side. If one side shows half a picture it means the other is shorted, i.e. bad LCD panel sorry it can't be fixed."

Hello,

Ok, I removed a flex cable from the t-con, nothing. I removed the other flex cable side, nothing.

I shined a flashlight to the screen, I do not see anything, its completely black.

I did see that post #3 from tom66 he mentions about a fuse on the t-con. I checked continuity on both of the t-con boards I have and they are fine, but when I measure voltage while the TV was ON, I did not get any readings. Can someone confirm if I'm suppose to be getting any reading? According to the fuse info displayed on the t-con it shows 125v / 3a.

Also, can someone gimme a hand how to test the transistors?

I'm attaching four pictures. One showing the two t-cons I have and the other 2 pics (one with flash / one without) is the back of the power supply I got online which it gives me all the correct readings I have done (not including transistors), and front of the power supply.

Thanks

[tom66]

Re: samsung UN46D6050 sound but no picture

You should get usually 12V both ends, can you try checking both ends of the fuse to ground on the resistance range, you are looking for a short (use 200 ohm range if you have a manually ranging meter)

[rlega]

Re: samsung UN46D6050 sound but no picture

You should get usually 12V both ends, can you try checking both ends of the fuse to ground on the resistance range, you are looking for a short (use 200 ohm range if you have a manually ranging meter)

I got 12v reading on both t-cons.

So my question is this, eventhough I see the backlight turning ON when I turn on the TV, and when I change channels, what else gives light to the screen?

If its the backlight, how come I see it ON?

With the TV on standby, I disconnected the cable that goes from power supply board to the mainboard and the backlight came on.

As you can see, I'm trying not to give up on this TV until I have no other test to perform.



Thanks

[nomoresonys]

Re: samsung UN46D6050 sound but no picture

its a head scratcher, maybe try a firmware update?

[CapLeaker]

Re: samsung UN46D6050 sound but no picture

If you removed one of the ribbon cables coming from the T-Con to the LCD panel, with the lvds cable from the main board plugged in and the screen stays black, that sounds like the LCD is bad. Maybe you could borrow an oscilloscope and check the main board for video to narrow it down some more?

[tom66]

Re: samsung UN46D6050 sound but no picture

There's a small chance you could have corrupted firmware - but I thought you had tried to swap the main board over? That would eliminate any concerns about corrupted firmware...

[nomoresonys]

Re: samsung UN46D6050 sound but no picture

depending on how many boards you tried, you may have bought a bad one, its easy to get a bad board from ebay, I would still try a firmware update if you can find one. but some tvs you need to see the menu before you can update.

[nomoresonys]

Re: samsung UN46D6050 sound but no picture

repair kit, maybe check/test those 8 parts out real good. http://www.shopjimmy.com/samsung-bn4...repair-kit.htm

[rlega]

Re: samsung UN46D6050 sound but no picture

@CapLeaker - Yes, the screen stayed black. I used a flashlight, and nothing is displayed on the screen.

@tom66 - correct, I purchased a broken screen TV and I was able to use the mainboard from that broken screen TV, problem persisted.

@nomoresonys - The only board I purchased was the power supply. The TV I purchased with broken screen had the same mainboard and t-con, but not the power supply board, so after replacing those two parts that were the same, the problem persisted, then I purchased the power supply board online, and the problem still there.

I saw that repair kit, but can someone gimme a hand how to test those? I have tested the fuse and resistor and they are OK. How to test the rest?

I'm leaning towards what you guys have said already, bad LCD panel.

Thanks, I really appreciate it.

[tom66]

Re: samsung UN46D6050 sound but no picture

So, with the cracked panel, the TV had a part picture? (you should have been able to see some pixels still work)

[tibimakai]

Re: samsung UN46D6050 sound but no picture

Tom is right, you should transfer your boards, to the broken one and see if something it's happening.

[nomoresonys]

Re: samsung UN46D6050 sound but no picture

yep, I third the motion.

[rlega]

Re: samsung UN46D6050 sound but no picture

Hello everyone,

I took some voltage readings. I hope you guys understand it. I do not understand the legend on the power supply board. Perhaps someone can let me know if the readings are OK.

Thanks

[budm]

Re: samsung UN46D6050 sound but no picture

OK, it uses CN803A (16 pins connector, CN803 is 14 pins connector),
All the pins that you labeled are the ODD number pins, 1, 3, 5, 7, 9, 11, 13, 15.
So according to the chart for the ODD number pins, the Voltages look OK,
You cannot get to the EVEN number pins, you have to probe on the bottom side of the board, there is Voltages chart for the EVEN number of the CN803A.

[rlega]

Re: samsung UN46D6050 sound but no picture

Thanks budm,

The bottom pins voltage are as follow. I inserted my digital voltmeter point lead on the white connector while the TV was on and that's how I got the even pins volatges.

That's what I understood from your reply.