Samsung LCD power supply board has died 4 times in 15 months

Ivan_P

Commendable
Mar 7, 2016
4
0
1,510
Hi,

I'm posting here to seek answers because I am very worried about this and puzzled as to how such a thing could happen. Long story short:

I got a H8000 in October 2014. In just a little over 30 days, in November 2014, one morning I went to turn the TV on and it did not. No standby light, no image, sound or noise or any sort. It was completely dead. Got upset naturally and after contacting support, and the repair guy visit to diagnose the problem, they replaced the power supply board. They didn't know what caused it.

Fast forward to March 2016. Since the initial repair the same part has been replaced 3 more times. It happened every 3-6 months in that time frame and every single time I wasn't given an explanation as to what happened... they didn't know why it happened. The last time it only lasted a little over a month. Now they have decided to give to credit for yet another replacement.

I even bought a UPS thinking it might help even though I never had this problem with my previous TV the ES7100. I got a CyberPower OR700LCDRM1U because of its thin design fits perfect on my home entertainment table. It's not pure sine wave, but I was told I shouldn't worry to much about that on TVs and I see no reason how this could be the problem. My cable box and Samsung 7.1 surround sound system are also hooked up to this UPS (surge only) without issues.

I also read in Samsung's support website that they do not recommend leaving your TV plugged in for longer periods of time without use (like going away for vacation) and that you should unplug the power cable in those cases until you watch TV again. I do not watch TV daily and sometimes 1-2 months would pass without turning on the TV. This baffled me, because it is inconvenient and you wouldn't expect that from a higher-end product, but I want to confirm if this could cause my issue.

The replacement arrives tomorrow and it is a JS9000. It is a nice upgrade and before I even plug it in I want to be sure that what happened with the H8000 was just a struck of very bad luck. The extended warranty expires later this month and just to think the same thing is going to happen makes me almost depressed. I read researched about Samsung having a capacitor problem for years. How is it possible they sent multiple PSB with the same problem over and over and not fix the core of the problem? Moreover the capacitors were inspected and they seemed fine with no visual damage.

This is what makes me unsure so to what really happened. All repair guys thought there was something wrong with the unit that they couldn't figure out what it was. Apparently something else outside the PSB was causing the part to malfunction and go bad after some time with 100% certainty.

Any input is appreciated. Thanks!
 

mjslakeridge

Distinguished
I have had power supplies fail on Tvs and computer monitors over the years, but only after many years of heavy use. In each case it was definitely the capacitors, because when I took it apart, multiple capacitors had bulged tops, and some had fluid leaking out. I was able to solder in new caps (Japanese, not Chinese), and the units are still going strong.

So I suspect something in your TV was causing the PSB to fail, especially after such a short period of time. Hopefully you will have better luck with the new TV!
 
I highly doubt the un-plug admonishment is other than a best practice kind of a thing, UNLESS such TV has a fan and it only comes on when it's turned on and the PSU self-cooks when idle. Still a modern PSU should be able to standby forever by convection only cooling, UNLESS this particular TV is of a particularly bad designed.

The cap problem is years old, that problem should no longer exist.

They are giving you a new model, that's good.

If this happens again, I suggest research whether your locale has a lemon law and if so, ask for a refund.

Is the TV mounted atop a fireplace? does it have enough ventilation? Is there a brown patch up on the ceiling directly above the TV?
 

budwich

Honorable
Oct 30, 2015
205
0
11,160
"Good" tech's can readily trouble shoot power supplies in terms of determining what circuit / voltages are missing and what components contributed to the problem. Having multiple boards having a similar "fault" should even be better in providing the "test bed". Of course, "good" usually shows up IF they have the time / given the time to do their work. Without knowing what the failure actually was, you are "shooting" in the dark. Hopefully your new set won't have a problem.... but it certainly is suspicious that the failure repeated so much. As for unplugging, good luck. I suspect out side of those worried about being "green", I doubt anyone unplugs their appliances when not in use whether its for a short or long time. The biggest concern would be if your power grid is so unreliable that there are numerous "events" such that your house is being hit with unexpected line "items" on a regular basis... then you have other problems.
 

Ivan_P

Commendable
Mar 7, 2016
4
0
1,510
Thanks guys. I really appreciate your answer. The TV isn't mounted on a wall o near a fireplace, just sits on its stand on a home theater table. And I agree... the techs didn't seem all too knowledgeable about diagnosing the problem with PSBs or maybe they didn't want to put in the effort.

Good to know I don't have to unplug my TV. If the same thing happens with this one that's surely a sign that something is wrong somewhere with the power coming in, but that would be an extremely rare case as my power grid has proven stable for years and no issues experienced with other equipment in the house. Hopefully it is just as you said and I have nothing to worry about and will have good luck with this one!