Re: Samsung UN50J5200AFXZA - Screen goes blank

It's only 50", but still, yeah, a nice TV and with half of it working so we know the boards are all good it sure would be nice to put it back in service.

What would be the minimum resistance value that would tip me off to any bad caps?

Re: Samsung UN50J5200AFXZA - Screen goes blank

Well I have to admit this vocabulary is new to me here but I am assuming the tab bonding boards are those long narrow boards which are connected directly to the T-CON board, is that not correct?

If so, then yes, they are pretty much completely exposed along the bottom edge of the rear of the unit without pulling the frame. They have ribbon cables that do a 180° bend up under the frame and from there I can't see what's going on but I've been assuming those are fastened to directly to the panel.

Re: Samsung UN50J5200AFXZA - Screen goes blank

I am totally prepared to separate the frame, like I said I just need to clear a little space first.

I've never tried replacintg SMD caps but managed to do a couple of SMD microswitches on a laptop touchpad recently. I have a variety of soldering irons and a quality heat gun with nozzles.

I've probed most of the caps on that board and haven't found any with less than at least 0.7K ohms.

Re: Samsung UN50J5200AFXZA - Screen goes blank

Not really clear what I'm looking at here. Is it just that the tab where it's bonded to the panel is sandwiched between parts so you can't get at it?

Soooo...TV's junk then?

Re: Samsung UN50J5200AFXZA - Screen goes blank

Would this be a case where renewing the tab bonds might feasibly fix it? I've never tried that but I've done a couple of Android phone screens. I've got appropriate heating equipment and a high quality FLIR camera.

Just going to need to clear a bit more bench space before I can separate the panel from the frame.

Re: Samsung UN50J5200AFXZA - Screen goes blank



Thanks very much for the response. Please see attached photos:

1- Entire rear panel
2- Power supply board
3- Main logic board
4- T-CON board
5- Panel bond board (left side from rear of TV)
6- Display with left (from rear) panel bond board disconnected from T-CON board

When I removed the LEFT (from rear) panel bond board connection, the opposite side (LEFT from front) of the TV display appeared to work normally - this is the first time I've seen any image...

I just picked up a free Samsung UN50J5200 that seems like it should be worth saving. It powers up but only briefly displays a gray bar across the top 2" of the screen, which gradually fades to black starting at one side and working across the screen over a period of less than a minute. After that, nothing.

The backlights work and stay lit indefinitely.

The power supply puts out in the range of 12V to the main board, but curiously the DC voltage to the LEDs is very high - like over 200VDC. Is that normal? I would expect more like 40VDC. Is it just a really long...

Re: New Members - please post your introductions here

Ha, just noticed the post right above mine is about the exact same TV. Good luck to you with that Shawn...look for a group of five 3300uf electrolytics on the main power board - mine were obviously toasted and total repair time was less than 30 minutes start to finish.

Re: New Members - please post your introductions here

Just a quick intro post in order to gain access to all this forum has to offer. I'm an energy efficiency engineer by trade, with very little electronics training but I'm a hardcore tinkerer at heart and can't resist taking apart broken things to see if I can get them working. Currently working on a Vizio VP50HDTV20A that was given to me with bad PS caps. I replaced those and it fired right up but still has a handful of annoying one-pixel wide vertical lines running the entire height of the screen. Every source I can find says...