Samsung LE32M51B S black screen

[intenzive]

Hello,

recently a friend of mine gave me a Samsung TV with an issue. Actually it's a strange issue. The TV turns on, I can see the backlight and I can hear the sound but there is no picture on the screen. As I said the backlight is working because I can see it when I power it on but there is something interesting. When there are changes in the signal for instance the picture is changing from
black to white I can see that something is changing on the screen. It flickers there is no picture. Any ideas? I'm posting some pictures of the TV PCB's.

[budm]

Re: Samsung LE32M51B S black screen

Can we see the pictures of the whole back side of the TV so we can see how all the boards are connected together?
So you see the backlights are on and you have glow on the screen? Screen shot of what is shown on the screen? Washed out pictures?

[intenzive]

Re: Samsung LE32M51B S black screen

There are no washed out pictures. Just sometimes I see like the backlight is becomming brighter and darker maybe when the scenes of the channel I am watching is changing. On the screenshots you can see what can I see.

[budm]

Re: Samsung LE32M51B S black screen

OK, thanks for the pictures.
We need to check the T-CON board next so we need good clear pictures so we can see the Voltage test points on the board. You can also try reseating the cables.

[intenzive]

Re: Samsung LE32M51B S black screen

Reseating the cables didn't change anything. This is the t-con I suppose with better resolution:

[intenzive]

Re: Samsung LE32M51B S black screen

Some more pictures with good quality:

[budm]

Re: Samsung LE32M51B S black screen

Please see the picture, there are 3-pin Voltage regulators that you also need to check the report the readings of all 3 pins.
You can also try having just one white ribbon connected one at a time to see what you will see on the screen. At this point I suspect bad T-CON board.

[intenzive]

Re: Samsung LE32M51B S black screen

Please see the picture, there are 3-pin Voltage regulators that you also need to check the report the readings of all 3 pins.
You can also try having just one white ribbon connected one at a time to see what you will see on the screen. At this point I suspect bad T-CON board.

You mean to check every pin one at a time with ground to see the voltage on the Voltage Regulators? "The white ribbon" you mean the 2 ribbons going to the LCD? And what about the other red circles you've put on the image. To check the voltage the same way?
And something else. My friend told me before stopping completely the TV was starting with maybe white horizontal lines on the screen but he is not sure about this because it was long ago.

[budm]

Re: Samsung LE32M51B S black screen

Black probe on the chassis.
Yes, the Voltage on each pin of those 3-pin devices.

"The white ribbon" you mean the 2 ribbons going to the LCD?" Yes.

[intenzive]

Re: Samsung LE32M51B S black screen

Black probe on the chassis.
Yes, the Voltage on each pin of those 3-pin devices.

"The white ribbon" you mean the 2 ribbons going to the LCD?" Yes.

Thank you very much for you fast answers. I will check those tomorrow and report the results here. Thanks once again for the help

[intenzive]

Re: Samsung LE32M51B S black screen

I've marked the results on the following image:

[budm]

Re: Samsung LE32M51B S black screen

Fuse CP101 ('P' on top) to the right of the LVDS connector is open.
What is the LCD panel number so you can look up the spec sheet? It will tell you what the T-CON current draw and the inrush current are, typically about 3~4A range.
You can temporary solder in 3A fuse with leads to test, no need to remove the old fuse.

[intenzive]

Re: Samsung LE32M51B S black screen

Fuse CP101 ('P' on top) to the right of the LVDS connector is open.
What is the LCD panel number so you can look up the spec sheet? It will tell you what the T-CON current draw and the inrush current are, typically about 3~4A range.
You can temporary solder in 3A fuse with leads to test, no need to remove the old fuse.

I measured the resistance between the two pins of the CP101 and it is zero, so I think it's not open. This is the LCD panel number:

[budm]

Re: Samsung LE32M51B S black screen

So do you get the 12V on the input side of the fuse? The TV is on when you make the measurement?
If there is no 12V on the input side of the pin then the main board is not sending the Voltage to run the T-CON.

[Dang]

Re: Samsung LE32M51B S black screen

I have this Tv and I found the fuse to give a reading of about 70 ohms, simply removing it and replacing with a temporary solder bridge rectified the issue, I'm not saying this will help you but your symptoms are pretty much what I was having.

[Dang]

Re: Samsung LE32M51B S black screen

The blue s/n sticker to the left of the LVDS connector looks melted on one end, is there anything obvious around that area?

[newtothis]

Re: Samsung LE32M51B S black screen

Replace that bridge with the correct fuse or risk losing the set

[Dang]

Re: Samsung LE32M51B S black screen

We all love to fix things here, me included but there comes a time where it just isn't worth it, looks like this card can be had for just under £4 on Ebay.

http://www.ebay.co.uk/itm/LVDS-FOR-P...item43cb1d5e91

[Dang]

Re: Samsung LE32M51B S black screen

Your right newtothis, been a year and still fine, it only cost a tenner so I may well listen to my own advice, £4......

[newtothis]

Re: Samsung LE32M51B S black screen

lol