Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

I was able to successfully de-pin both B5V terminals from the main board connector....piece of cake! I was sure to isolate them from the chassis and each other before taking readings.

B5V is still absent from the PSU

[budm]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

B5V and B13V are switched power supplies that will not be present until PS-ON from the main board is present to the power supply board to turn them on.
The power supply board has pull-up resistor to keep the PS-ON pin of the power supply HI, but when the MD is connected to the PS board, that PS-On line is kept LO by the MB, it should let the PS-ON go HI when TV is turned on but that is what the MB not doing right now..

[MASTER_TECH_101]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

No need go through all this nightmare of troubleshooting.
99% of time this board has bad Flash IC

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

B5V and B13V are switched power supplies that will not be present until PS-ON from the main board is present to the power supply board to turn them on.
The power supply board has pull-up resistor to keep the PS-ON pin of the power supply HI, but when the MD is connected to the PS board, that PS-On line is kept LO by the MB, it should let the PS-ON go HI when TV is turned on but that is what the MB not doing right now..

Sorry I had them backwards. A5V is the stand-by line. Thanks budm. No luck on a schematic for this board here either.

No need go through all this nightmare of troubleshooting.
99% of time this board has bad Flash IC

Are you referring to the main EEPROM?

[Dannyx]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Are you referring to the main EEPROM?

Nope - flash IC is the NAND flash. The square chip right above the optical connectors if I'm not mistaken.

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Nope - flash IC is the NAND flash. The square chip right above the optical connectors if I'm not mistaken.

That chip looks like its BGA. If this is bad and that is the case it looks like I'm SOL for fixing this one without a re-work station?

Has anyone come up with a schematic for this or have any further pointers? Thanks everyone

[Dannyx]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Yes it is BGA, but even if you had a rework station, obtaining a similar chip + programming it would probably outweigh the price/effort of a new board entirely. Common fault, not worth bothering IMO.

[nomoresonys]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

55 inch, nice size, worth a board I would say.

[Dannyx]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Yes.

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

55 inch, nice size, worth a board I would say.

Yes.

I agree with both of you, completely. The TV itself is in premium condition, not abused and super nice otherwise. It is missing the remote tho.

Here's my issue, I bought it this way not knowing if the flap is any good. I can tell when the backlights come on it isn't cracked, but I've never seen it work. The board is big $ for an old TV, about $170.00 laid in minus the core charge. On the other hand....at least it's still available new! lol I'm not sure I'd trust a used board unless it was from my own stock and got a good trial run before selling it.

https://encompass.com/item/9820929/Samsung/BN94-06969A/

Add that to the $20 I gave for it and another $10.00 for a remote and this would be my cash investment.

I believe at best this TV is worth no more than about $250.00, even though its 240hz and smart, but those features aren't as valuable as 4K and faster processing. With some of the new pricing I'm seeing that $250 is more likely going to be $225 or even $200 locally.

When I look at risk v. reward I think the risk is too high to pay any more than $50.00 for a good working board. The two used ones I found online are twice that and none of the repair services offered seem to cover this symptom. Finding a whole TV with a busted flap and a good main board are long odds.

The first three commandments in what I do are "Thou shalt use integrity with wisdom", "Thou shalt use Flux" and "Thou shalt double their money". I don't want to sound like a greedy jerk or nothing but in my opinion if I can't double up it may not be worth it.

Does anyone feel my opinion of the TV's value is under or over the mark? Does it make sense to everyone else to double up or go home?

At the present I'm inclined to put it back together, wait for a parts TV and see if there's a greater power than odds to help me out. It wouldn't be like this hasn't happened before.

Like the odds of finding a 2011 Samsung B650 plasma for parts right when I was working on another one, add the longer odds for it coming from McAlester OK some 225mi away, being a fully working TV with the exact part number main board I needed, all of it's original stickers still in place and a stand in surprisingly perfect condition considering it came from a recycle house.

I've faced the longest of odds before....more than anyone knows....yet it always works out and here comes an answer.

Does anyone have further advice, other than to replace the main board? I tried heating the chips, maybe I'll try some freeze spray on them and see if there's any change. I'd hate to throw in the towel if someone might have an idea!

[nomoresonys]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

I agree, the used market is tight, might be better off parting it out, definitely doesn't justify a new board at 170, like you said no meat left on the bone.

[budm]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

I believe Nick's TV offer repair service for the main board, you may want to contact him.

[monybito]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Hi all, I am looking for a bit of help. I have a Samsung UN55F6350 LED. The Screen will not turn on, I have audio. Already replaced the Tcon board, that wasn't it.
I was checking the standby voltage and wasn't getting any on the Power Board harness (plugged in)
while still plugged in, but tv OFF, I unplugged the harness from the Power Supply board to the main board, as soon as I did that the SCREEN turned on - that means my LED's are good... what is wrong, Main board or Power Supply board? assistance would be greatly appreciated.

[Dannyx]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

So BL_ON is not present at the pin when the main board is connected and TV is on (has sound) > bad main board I would say. Depending on your skills and how much effort/time you wish to invest in this board, you could try searching for a schematic for the board and tracking down the BL_ON signal.

Alternatively, as a quick and dirty "fix" you can "cheat" by pulling out the BL_ON pin from the plastic socket at one end so the pin is floating. That way, you'll have the backlight on all the time Do this first to check if all other functions are working correctly.

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

I still have yet to find a main board for mine. They're scarce as hens teeth!

[monybito]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

check shopjimmy.com they have both the powersupply and main boards.

[budm]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

So BL_ON is not present at the pin when the main board is connected and TV is on (has sound) > bad main board I would say. Depending on your skills and how much effort/time you wish to invest in this board, you could try searching for a schematic for the board and tracking down the BL_ON signal.

Alternatively, as a quick and dirty "fix" you can "cheat" by pulling out the BL_ON pin from the plastic socket at one end so the pin is floating. That way, you'll have the backlight on all the time Do this first to check if all other functions are working correctly.

+1 on the quick and dirty fix, if everything else are OK then you can use other control signal to simulate BL-ON.

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Just wanted to update this thread. I ordered a main board that should be here tomorrow, so I got the TV on the bench and figured "what the hell, let's bake this turd"...so I pulled the main board and baked it for 10 minutes at 380 degrees. Low and behold the stand-by light came on. Not only that it responded to the remote. The TV did not turn on fully but when I hit the power button on the remote to turn it off the stand-by light quit flashing and went solid on.

I just baked it again at the same temp for 12 minutes. Guess we'll see what happens.....

[DXseekerMO]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

No taco. Will update when the board goes in.

[diif]

Re: Samsung UN55F6300AFXZA appears dead, stand-by present, main board suspect

Just wanted to update this thread. I ordered a main board that should be here tomorrow, so I got the TV on the bench and figured "what the hell, let's bake this turd"...so I pulled the main board and baked it for 10 minutes at 380 degrees. Low and behold the stand-by light came on. Not only that it responded to the remote. The TV did not turn on fully but when I hit the power button on the remote to turn it off the stand-by light quit flashing and went solid on.

I just baked it again at the same temp for 12 minutes. Guess we'll see what happens.....

It's not a cake, it is not being baked you are trying to reflow the solder under the processor.
Lead free solder needs a bit more than 200c to melt.
Not that I suggest putting a board in the oven especially one for food.