Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Quick question:

I'm getting 5.7v on the PS connector that leads over to the main board. So that is fine. But when I pulled the two other connectors on the PS that both lead directly to the panel itself I get 0.0v on every pin.

Does that mean that the PS is not providing voltage to these connectors or could it mean that the tv senses the connectors have been pulled and it then automatically denies voltage at the PS level so that it never reaches the connectors in a purposeful way as the tv tries to protect itself?

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Wondering if anyone can provide an answer to that last question as it pertains to this particular model of television (Samsung UN60F8000BFXZA).

I’m trying to determine if the LED panel itself has stopped working as opposed to the Power Supply board being the culprit.

~ kca

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Given the pictures I posted earlier, does anyone know how I can safely force the backlights on re: this particular model Samsung tv?

I would like to prove or disprove that the backlights are still functional. What would be the exact steps that it would take to jump them on?

~ kca

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

It's a samsung, if you unhook the cable from powerboard to maqinboard, leave it off, plug power cord into wall if backlights do not come on and stay on there's problem before the mainboard, meaning problem in the powerboard or backlight/backlight circuit, if they don't come on wiggle the wiress a little going from powerboard to panel, just to check if there's a problem there.

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Yes, that is what I established a few days ago. No backlights appear. So now I’m trying to determine if the backlights are indeed functional before I either replace components on the PS board or just buy a new PS.

I can get a power supply board for only $42, but I want to prove that the backlights are operational before considering the PS purchase. I’ve read several posts that explain that the backlights can often be jumped on but I don’t know exactly which pins / resistors / boards to employ. Or, maybe none of that would work given the current symptoms? That’s what I don’t know but would like to try if it’s doable.

~ kca

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Can you post a good clear picture of the legend/map of the connector there, looks like the one on the corner of the board.

[lotas]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

It's a samsung, if you unhook the cable from powerboard to maqinboard, leave it off, plug power cord into wall if backlights do not come on and stay on there's problem before the mainboard, meaning problem in the powerboard or backlight/backlight circuit, if they don't come on wiggle the wiress a little going from powerboard to panel, just to check if there's a problem there.

This trick does not work on some models.

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Does it on this one, can you tell if it has pull up resistors?

[lotas]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

I don’t remember on this model and I don’t have it for repair now.

[Storyteller12]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Yes, it works on this model also.

[lotas]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

This model (xxF8000) does not have a simple power supply; it has a built-in programmed controller that controls the backlight.

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Ok, interesting, I'm not familiar with this one, wonder if the force on is basically the same as most?

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Here are the pertinent images of the PS board we're discussing:

Photo #1 = Entire PS
#2 = top left (primary) connector voltage chart
#3 = middle left connector chart (heads out directly to one of two LED cables)
#4 = bottom left connector chart (heads out directly to the other LED cable)
#5 = image of the two “twin” LED cables themselves

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Ok, take it slow, #2 with cable from powerboard to mainboard unhooked, check the pins voltage 1-27 can skip grounds, which pins have voltage and how much.

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Yes, it appears this model’s PS is designed to supply voltage directly to these dual LED cables via the two connectors. As I mentioned in an earlier post, the readings on both the middle left LED connector and the bottom left LED connector are 0.0 on all of those pins.

In other words, it appears that the PS is failing to supply these LED connectors and cables with the necessary voltages. But, could it also be that the failure of the backlights themselves might cause the voltages to be denied to these two LED connectors because the tv recognizes the backlights are not functioning (or not functioning properly) and it therefore denies voltage to the LED cables because it’s attempting to protect itself from further damage?

This is why I’m trying to fire up the backlights in any other, logical way to prove to myself that the backlights are not the problem and that the PSU, definitively, is the issue.

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

We can try it, if you make sure you use resistors for the connections you shouldn't blow anything up.

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Do post #34 first.

[nomoresonys]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Here's a good video from Bobby, might help, see if you can understand it: https://www.youtube.com/watch?v=qIue5Sd6fzE

[kca]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Okay. I’ll check them all again and list them in the next post.

In my original post, I didn’t make it perfectly clear but I had tested all of these pins (1 through 28) and the only one I found suspect was that SDA line I was discussing earlier in the thread. I’ll post exact voltages for all 28 pins to help clarify all of that.

[lotas]

Re: Samsung UN60F8000BFXZA ~ No Picture or Sound - 5 Res Light Blinks

Here's a good video from Bobby, might help, see if you can understand it: https://www.youtube.com/watch?v=qIue5Sd6fzE

This is a plasma power supply, it's completely different and it doesn't have a backlight.