Samsung UN50KU6300F constant reboot, bad backlights?

[nomoresonys]

I hear you, God forbid a gecko gets in the house and starts bumping into the tv. tv gone

[x_orange90_x]

I hear that, wish I had a time machine, could go back and just refuse to buy any tv with these damn flimsy easy to crack as an egg shell and ALWAYS prone to shorting panels. They have better resolution and are bigger and lighter than the old crt but not nearly as reliable.

They keep making the panels thinner too. I feel like my dent pullers are even too much sometimes for these panels. I get that they want TV's to be lighter, but today's 70" tvs only weigh 40lbs at most! At this rate, crazy-flying house flies will be cracking our screens in the near future!

[bohaboha]

Here's the clip

don't see anything on video

[nomoresonys]

I hear that, wish I had a time machine, could go back and just refuse to buy any tv with these damn flimsy easy to crack as an egg shell and ALWAYS prone to shorting panels. They have better resolution and are bigger and lighter than the old crt but not nearly as reliable.

[x_orange90_x]

It would be nice if they could all be fixed simply with a component or 2, but unless you work with them a LOT, it can be a real pain to figure out. Just had to retire a good old samsung ccfl from 2007, couldn't figure out the powerboard fault. Could have bought a replacement but had the back off so many times, there was nothing left of the plastic screw receivers to hold the back on and I'm always pretty careful not to over-tighten. Screwing metal into plastic it's so damn easy to strip it out, should stop at the first sign of resistance, beware using power screw drivers. A lot of manufactures have REALLY cheaped out lately, was recently looking at a Hisense 55-Inch Class A6 Series 4K UHD, cheap one board piece of shit, all plastic so the one board has to screw into plastic with a little piece of metal sitting on there, that's suppose to do the grounding I guess, is what they're thinking, shabbiest construction I have seen lately. Wonder if anyone started a thread topic on cheapest made junk they have seen, this hisense fits there. Small wonder I prefer the older tvs that actually use some metal in the construction.

Wow that one does sound cheap! I cracked a Samsung curved trying to open it because the entire back is screw less. It snaps together all over and it wouldn't let go in one of the corners so the screen fractured.

A tip that usually works for me with screws is to turn it backwards slowly until you feel it drop in the groove of the thread. It usually makes a slight click sound. Then you know you're in the thread.

Putting this particular tv back together the other night was a pita because none of the corners wanted to live up with the screw holes. It was like it shrunk while it was off.

[nomoresonys]

It would be nice if they could all be fixed simply with a component or 2, but unless you work with them a LOT, it can be a real pain to figure out. Just had to retire a good old samsung ccfl from 2007, couldn't figure out the powerboard fault. Could have bought a replacement but had the back off so many times, there was nothing left of the plastic screw receivers to hold the back on and I'm always pretty careful not to over-tighten. Screwing metal into plastic it's so damn easy to strip it out, should stop at the first sign of resistance, beware using power screw drivers. A lot of manufactures have REALLY cheaped out lately, was recently looking at a Hisense 55-Inch Class A6 Series 4K UHD, cheap one board piece of shit, all plastic so the one board has to screw into plastic with a little piece of metal sitting on there, that's suppose to do the grounding I guess, is what they're thinking, shabbiest construction I have seen lately. Wonder if anyone started a thread topic on cheapest made junk they have seen, this hisense fits there. Small wonder I prefer the older tvs that actually use some metal in the construction.

[vinceroger69]

Nice to hear you have fixed the tv and another saved from landfill

[x_orange90_x]

Glad to hear it, Indeed when you figure all the time that can be spent trying to troubleshoot, if a board is available for a fair price, it sure can be the best way to go, it may also preserve a little sanity, lol.

Preserve sanity is right! I got pretty pissed at spending ALL that time and it did exactly the same thing. Thank you for all your help and guidance!

[nomoresonys]

My guess is the backlight driver IC on the non-working powerboard may be bad, seems like you checked everything else.

[nomoresonys]

Glad to hear it, Indeed when you figure all the time that can be spent trying to troubleshoot, if a board is available for a fair price, it sure can be the best way to go, it may also preserve a little sanity, lol.

[x_orange90_x]

I gave up on diagnosing the original board and just ordered one from eBay. I put it in last night and the tv is working great.

My advice to anyone else with this model power supply is to just get a replacement. There's too many things that fail on it and getting it working may only buy a little bit of time before another component fails.

[x_orange90_x]

It looks like it can't be either of those. 600 M ohms would be a huge resistor, and from what I'm finding .06 ohm doesn't even exist.

I can't find a schematic for this board either

Edit: wow this is frustrating. I can't find a schematic, therefore I can't see on paper what the value is supposed to be. Likewise, searching for the board number and "R9022" turns up absolutely nothing. And to top it off I'm finding this exact same model board with a completely different 5 band resistor instead of the 4 band I have.

[x_orange90_x]

Double check the resistor value using one of the many available websites.

using the tool on DigiKey I get either 600M ohms or .06 ohm depending on the color is the third band, which I'm not positive if it's grey or silver. Can you tell what color it is?

Also, my reading of 0.00 ohms means my resistor is bad, right?

Edit: it has to be silver because that's .06 Ohms. Grey would be 600 MegaOhms. I can't however find a .06 Ohms resistor online.

[diif]

black, blue, silver, gold is correct. When I looked it up I got 600 M ohms. Maybe I did something wrong


I checked other resistors on the board and got similar oddball readings. I think the resistor ok. That one diode on the bottom has been mentioned on these forums several times as causing these symptoms. It's surface mount, so if I take it off to test I'd be replacing it as well.

Double check the resistor value using one of the many available websites.

[x_orange90_x]

I replaced the diode on the bottom and I STILL have the same symptoms!

Edit: I removed a leg of that resistor and checked it. It reads 0.00 ohm 😑

[nomoresonys]

Maybe there: https://www.aliexpress.us/w/wholesal....home.search.0

[x_orange90_x]

Absolutely, I do believe that diode is bad.

I'm trying to source a replacement right now. I'm going to call a local electronics store later to see if they carry these, but if they don't I'll have to order some. The SK310C I asked about is too far off spec wise. Comparison of those two are attached

Ir is blank on the datasheet for the SK310C.

[nomoresonys]

Absolutely, I do believe that diode is bad.

[x_orange90_x]

Is it black-blue-silver-gold, I get .06 ohms, if those colors are correct, then even 1.2 ohms is way out of specs, then as usual when a reading seems off in circuit lift a leg and check ooc.

black, blue, silver, gold is correct. When I looked it up I got 600 M ohms. Maybe I did something wrong


I checked other resistors on the board and got similar oddball readings. I think the resistor ok. That one diode on the bottom has been mentioned on these forums several times as causing these symptoms. It's surface mount, so if I take it off to test I'd be replacing it as well.

[nomoresonys]

Is it black-blue-silver-gold, I get .06 ohms, if those colors are correct, then even 1.2 ohms is way out of specs, then as usual when a reading seems off in circuit lift a leg and check ooc.