Hey all,
I know there's a lot of smart people on here, got an issue that I hope you can help me with.
I have an Samsung 60" plasma TV that's about 11 years old. It blew up a transistor in the power supply board. What do you reckon my chances of successful repair are?
Backstory:
Two weeks ago it shut off while watching and the power indicator was doing a double flash which indicates an error. I unpluged the TV and plugged it back in, it worked for a couple minutes then did it again. I unplugged it for 10 minutes, it worked for about 10 minutes before shutting down again. I left it unplugged overnight, then threw on a bunch of movies the next morning and it worked perfectly for over 6 hours. It was fine for the next two weeks, with maybe an hours worth of use every day. Today it died again. I did the unplug thing, and this time about 3 minutes after turning it back on it let out two loud pops (sounded like a bulb blowing) and shut down again. I opened it up and found an exploded MOFSET transistor on the power supply board. I was encased in this hard white stuff, maybe like a thermal paste? After scraping it off I could get a number off it and they're available on Aliexpress and Digikey.
I'm probably going to order one and see if that fixes it, but I have no idea if that's the only damage.
What are the chances something else is damaged? Am I wasting my time?
It's the only TV in the house, it would be nice to be able to watch some movies over the holidays. Should I go out and buy a replacement TV, keep this one as a spare (if I can repair it)?
As cheap as tvs are, I'd buy a new one. I'd try to fix this one out of curiosity, but not be in a rush.
I think soldering in replacement components or even swapping in a replacement power supply board would be worth a try, I'd say there's a 98% chance nothing else was damaged. The biggest risk might be damaging something when opening or closing the TV case, some modern TVs can be as tricky to get into as a smartphone.
Edit: 11yo plasma should be easy enough
Steve_Jones said:
As cheap as tvs are, I'd buy a new one. I'd try to fix this one out of curiosity, but not be in a rush.
1000% this. You can buy higher resolution TVs with faster refresh rates for like $500 all day everyday.
I think I paid $550 for my 4k, 65" Samsung in October of last year from Best Buy.
I would have stepped up to a 75-80" but I would have had to completely redo our current entertainment system setup to make one fit and didn't want to spend that much just yet.
In reply to z31maniac :
That 4K Samsung is now $429. It's crazy how cheap they have gotten.
Keep in mind that some of today's TVs are unusually cheap because they're smart TVs that are going to make money off of you by tracking you, spewing ads at you, possibly even for-real listening to your conversations now...I bought a 4K 32" gaming monitor a couple years ago on a Black Friday sale for around $270 and that's the cheapest I've ever seen one. That should say something about how much a display really costs.
Thanks for the input.
I think I'm going to pick up a 65" Sony X90L. They're advertised at CAD$1500 locally. The Hisense U6 and U8 models also look like great options for the money, but I'm more of a buy once and keep it for 10+ years kind of guy. Hoping that paying for the Sony name and quality control will prove to be the smarter long term choice. We don't have cable and only use the TV as a second monitor for my desktop PC, so Netflix and Prime Video are streamed though the browser. I don't use the smart TV functions. We've got a blue-ray player as well, but it rarely gets used nowadays.
I'd try fixing it. It's already berkeleyed; you're not gonna hurt it by trying.
Looks like an N-channel MOSFET. I'd try fixing it. It ain't exactly rocket science.
https://www.digikey.com/en/products/detail/onsemi/FDPF12N50T/1647283
Run_Away said:
Thanks for the input.
I think I'm going to pick up a 65" Sony X90L. They're advertised at CAD$1500 locally. The Hisense U6 and U8 models also look like great options for the money, but I'm more of a buy once and keep it for 10+ years kind of guy. Hoping that paying for the Sony name and quality control will prove to be the smarter long term choice. We don't have cable and only use the TV as a second monitor for my desktop PC, so Netflix and Prime Video are streamed though the browser. I don't use the smart TV functions. We've got a blue-ray player as well, but it rarely gets used nowadays.
11 years out of the Samsung, why switch brands?
There are two paths here for repair, one says the power supply just died and replacing the component will fix it. The other says *something else* killed the power supply and it will fry again. My suggestion, go to Best Buy or Walmart and spend $3-400 and move on with your only regret that it didn't break in time for the Black Friday sales.
In reply to triumph7 :
From my experience it's very rare for something else to kill a power supply and very common for power supplies to die on their own, I think replacing the power supply is a pretty safe bet.
In reply to GameboyRMH :
In 45 years working experience, it's not so rare. A lot of newer stuff does have some protection in the power circuits but it still happens.
I just broke the screen on a 55" Samsung. Probably 8 years old. I could pull the power unit for you if you want parts. Otherwise it is going in the garbage.
This has little to do with your situation as I'm sure it's an isolated event, but those plasmas are pretty fragile, even hidden behind lexan. I have a monster plasma at work that had a bad switching supply. I successfully replaced it, only to find out that while it was inverted on the bench, I broke the screen.
All TVs now are going to sell your info if you get a smart TV. Even some of the "dumb" TVs make you agree to a terms of use where it works with your cable/satellite provider to feed info back about your watching habits, but if you have a cell phone, a smart TV is a drop in the bucket when it comes to surveillance.
Don't stress over brands. Many TVs are sold under various names and some of them are just assemblers, not manufacturers. None of them will probably last 10 years anymore.
Thanks for all the advice guys.
I ended up ordering 3 replacement transistors from digikey, took them 36hrs from order time to my doorstep which is really impressive. Got busy with the holidays and didn't get a chance to try it out. Tonight I settled in and out the new transistor into place.
Everything went pretty smoothly, mounted it all back up and plugged it in. It did it's normal powering up clicks, then about 10 seconds later lots of smoke and arcing. Another transistor right below the original one exploded. So the exploding transistors are an effect of the issue, not the cause.
So at this point I think it's junk. Found one option for reman power boards, but I don't think it's worth it at $190USD + shipping.
https://www.ebay.com/itm/115816223667
I did end up getting a new Sony a little over a week ago, and we're really enjoying it so far. I was hoping if I could fix this one I'd put it in the bedroom.
Yeah I think a new power board would probably fix it (something else on the board is almost certainly what's causing the transistors to blow) but it's not worth the gamble since you already got a new TV. Maybe put it up for free/cheap on the local classifieds with a link to the replacement power board.
