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Samsung LCD TV LN-T5265F Black Screen Diagnosis Help

by gonefishin09 / September 15, 2009 5:57 AM PDT

my LN-T5265F stopped displaying video yesterday. It is out of warranty, so I am hoping to diagnose the problem myself before having an on-site service visit. I created a short demo video on Youtube here:
http://www.youtube.com/watch?v=ZVVUUAz78cI
Here is the sequence of events when I turn on the set:
-press power button, hear click, see blinking red LED
-after a couple of seconds, I see a faint glow from the set, i.e. it changes from black to a dark gray, so I think the backlight is on.
-at the same time the glow starts I hear a faint buzzing/crackling sound -- it sounds like very quiet electrical arcing (but I don't smell anything)
-a second or so after the buzzing starts, the video comes on very briefly -- less than a second, and then goes black. At that point, the buzzing stops, but the audio from the programming continues.
Have tried a total set reset with no change (not sure I did it correctly -- pressed remote control "exit" for 12 seconds, then down arrow, then enter ???) Have also tried unplugging for several hours with no change.

Is this enough info to make a definitive diagnosis of the problem? Maybe the power supply board? Or do I need to gather more info.

Thanks.

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more info -- found some fried capacitors
by gonefishin09 / September 15, 2009 2:38 PM PDT

since initial posting, I opened up the TV and had a good look at the power supply board (BN44-00150A), where I found three capacitors that were bulging and oozing brown crud. (Marked on circuit board as CM812, CM813, and CS804). They look just like the failed capacitors I've seen on computer motherboards from the early 90's when there was apparently a big problem with some kind of off-spec electrolyte. Anyway, I have located what appear to be matching capacitors on DigiKey (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=565-1504-ND) so am going to attempt to repair the board. Will post back results.

Does anyone have an opinion about whether I should replace the other similar capacitors on the board? There are two more of the same type that are not oozing, but I'm thinking if there is a whole batch of bad capacitors, then I may as well replace all five while I'm in there with the soldering iron...

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more info on faulty Samsung / Samwha capacitors
by gonefishin09 / September 18, 2009 2:20 AM PDT

in case anyone else stumbles across this thread, here is some more info about the faulty capacitors.
-They are branded "Samwha", which apparently is a company that took over Samsung capacitor manufacturing in 2002.
-The failed capacitors are series "WB". The current Samwha website indicates that this series was "obsoleted in 1999" (http://www.samwha.com/electric/templatedirs/guest/pro_discon23.html)
Exactly what "obsoleted in 1999" means isn't clear, but it seems strange that they were used on a TV manufactured in 2007. I found a datasheet for the series here: http://www.abcd-e.cn/abcd-e/www/a/products/capacitors/aluminum_electrolytic_capacitors/samwha/samwha_2006/wb.pdf They are described as "ultra low impedance" and have a high ripple current tolerance. The Samwha website identifies the "MK" series as their current replacement for "WB". http://www.samwha.com/electric/templatedirs/guest/product23.html

I found an almost exact specification match with the Nippon Chemi-Con KZE series http://www.chemi-con.com/files/KZE.pdf , specifically EKZE100ELL102MJ16S. I ended up ordering this instead of the KY series I linked to in my previous post.

I have since read on many posts that people have been successfully picking up off-the-shelf capacitors at Radio Shack or Fry's that are slightly over-rated, i.e. 1000uF, 16V capacitors apparently provide some additional ripple-current capacity than the 10V equivalent. Not being an electrical engineer, I'm not sure if there are any downsides to that approach, but fyi I had a look in Fry's this morning and they stock a 1000uF, 16V "ITE" capacitor for $1.92 which works out to almost the same total cost as I'm paying for 5 capacitors plus shipping from "mouser.com" (I decided to use Mouser instead of Digikey when I realized Mouser's Dallas-area distribution center is about 30 miles away, so UPS is next day for me).

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How do you remove the old capacitors?
by ktmart69 / June 12, 2011 12:33 AM PDT

Do you just clip them off?

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TV failure triggered by high humidity
by gonefishin09 / September 18, 2009 2:46 AM PDT

fyi... while googling this problem I came across perhaps 5 or 6 posts from users with similar symptoms who reported that the first occurrence of the problem coincided with some heavy rain or high humidity. Same thing happened to me. House had been sealed up all summer in air conditioning mode, so indoor humidity had been low and consistent. But we had some cool weather so I opened up all the windows, and then we had heavy rain, causing the indoor humidity to go way up. The TV stopped working within a few hours of the rain starting. My theory -- the blown capacitors are no longer sealed, so the high humidity can readily get inside, causing the already-degraded capacitors to perform even worse.

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Successful repair of power supply
by gonefishin09 / September 18, 2009 5:48 AM PDT

UPS guy came with the capacitors. Even with my amateur soldering skills I had them installed in about 10 minutes (I chose to do all five of the 1000uF, 10V capacitors, even though only three had failed)

After re-installing the power supply board in the TV, YEA!, it works again!

Samsung, if you are reading this, you really ought to initiate some kind of goodwill extended warranty program for these capacitor failures. After several days of Googling, it is apparent that this problem affects thousands of owners of many different models of Samsung TV. Clearly, this is a manufacturing defect. The fact that it doesn't typically reveal itself until after 1 year doesn't change the fact that the defect existed at the time of manufacture. As a minimum, an appropriate response would be to offer remanufactured power supply boards as a free exchange for ones with bulging capacitors. It would also be helpful to issue service bulletins that describe the problem and the solution (eg. specifying exactly what new capacitors should be installed) so that TV service people everywhere are prepared to fix this.

Swapping the boards is easy enough that many customers would be satisfied with just a free part, but probably most customers would rather have someone install it for them. Given that the set is out of warranty, most customers would probably be OK with paying something out of pocket for this. Personally, I would have gladly paid $100 to have someone take care of this for me rather than spend many hours researching the problem, ordering parts, and doing the repair myself. But the alternative that was offered to me by Samsung authorized service was to pay $100 trip charge, $100 repair labor, and $150 for a new power supply board, for a total of $350. It just isn't acceptable that Samsung expects customers to pay that kind of money to correct this manufacturing defect.

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photos posted
by gonefishin09 / September 18, 2009 1:00 PM PDT
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Replaced PS Capacitors
by lackmanm / October 10, 2009 10:09 PM PDT

gonefishin09,
Thank you so much for your informative posts. My LNT5265F has been displaying the classic problems described by many owners: multiple power up cycles, pink dots down the screen once it does power up and over time just a black screen. Samsung denied any issues when I called for support and said they have no known problems that are wide spread based on what I described. A new PS board is $150 to $200 plus service costs. Yesterday, I took my TV apart and found that two of the three 1000uf 10V capacitors that you described had failed (buldged at the top). I went to RadioShack and purchased two 1000uf 35V capacitors (35V was the lowest voltage that they carried. They are slightly bigger than a 10V capacitor, but they fit on the board) After soldering in the new capacitors and putting the TV back together, everything is back to normal. The capacitors were $1.59 each. Thank you for sharing the detailed information in your posts and saving me hundreds of dollars.

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Thank you!!!
by dcrb42 / October 15, 2009 1:33 PM PDT

We came home today, turned on our Samsung 46" LCD tv, no picture, just sound. We contacted Samsung who in turn had a certified repair service call us. The service guy was extremely rude. He wanted to charge mileage, even though we are in the same city, plus $35 fee for us being out of his area, and set fee for the call. That is without even looking at the tv. I searched the internet and found this forum and your post. We have our tv working and saved hundreds of dollars. My husband and I thank you, thank you, thank you!!!
My husband went to Radio Shack to by capacitors. He was surprised when the salesman asked him if we were repairing a LCD tv. The salesman said a man had been in that store the night before buying the same thing. Samsung needs to pay you!

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Samsung LNT4665fx/xaa
by valariemartin / November 2, 2009 1:29 AM PST

I have the same problem and don't have a clue as how to repair. Will the same capacitors fit for my 46 inch tv as your 52 inch? I can go to Radio Shack or order online. My additional problem is getting someone to do the actual replacement. Do you have any suggestions as to what type of tech person I need. My tv started taking 15 to 20 minutes to come on, then it just stopped coming on and just clicks. It was still under warrenty and they replaced 2 boards of some kind. Now a year later it's doing the same thing and Samsung, of course, will not take responbility. Any help you can give me will be appreciated.

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fixing your power supply
by gonefishin09 / November 2, 2009 4:09 AM PST
In reply to: Samsung LNT4665fx/xaa

If you can't do the soldering yourself, almost any person who has ever used a soldering iron could do the job. I read one post where a guy bought the caps at Radio Shack, and paid a kid behind the cash register $10 cash to do the soldering. If you don't know someone like that, you can either find an electronics repair shop to do the repair for you (check the yellow pages & call for a quote; some shops won't do little jobs like this), or you could replace the whole power supply board. They are available on the net for less than list price. eg. at http://www.encompassparts.com/ the board for my TV is about $105 vs.about $170 from Samsung. Installation takes just a few minutes. Philips screwdriver is the only tool required. In either case, I'd suggest you open the TV yourself to remove the power supply board; once you see the board, you'll know whether it has blown capacitors or not. If you see bad caps, you can be confident that either fixing or replacing the board should work. If you don't see bad caps, then I'd still suspect the power supply board but would order a new one from a place with a reasonable return policy so if you're wrong about the diagnosis, you'll be able to return it and hopefully only lose shipping costs.

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Same Problem
by Gojyumatt / November 2, 2009 5:15 AM PST

I am also having the same problem with my Samsung. when i turn on the tv i get a glowing black screen on every video input but i can here sound. after a couple of minutes the picture just appears! I have model number ln26a330j1dxza. I've already opened the back and found that 2 of the 3 capacitors are bulging. I know nothing about capacitors so trying to do the repair my self probably isn't going to happen, but i was able to find a new POWER BOARD for $65 and that looks very easy to replace. Is this my only problem?? Will i be allset after i swap out power boards?? please help!!!

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sounds like $65 well spent
by gonefishin09 / November 2, 2009 5:53 AM PST
In reply to: Same Problem

those bulging capacitors are definitely a problem, and very likely your only problem. That $65 board sounds like a good deal.

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new board?
by jvbluefish / November 2, 2009 6:24 AM PST

i question the reliability of a new board. reading other posts it looks like the boards that were replaced under the warranty all failed later after the warranty expired. do the new boards have the same low temperture caps. posts recommend upgrading to a higher temp. 105 degree c in lieu of 85 degree c.

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No recycled board.
by Gojyumatt / November 2, 2009 7:13 AM PST
In reply to: new board?

No all i could find were used and recycled boards. I called up the company and asked what a recycled board was and they told me it was boards from returned TV's that have been tested to work at the level of the original. To be honest I'm actually expecting it to break sooner or later. its just that money is very tight for me and the cheapest i could find someone to look at it was $75 and he said that he wouldn't replace the capacitors he would only find a new board and i would still have to pay for parts and labor. So i figured paying $65 for a whole new board would be a little cheaper and i also get a 30 day money back warranty on the part so if it doesn't fix the problem I'm only out $10 in shipping. So even though it probably wont be a permanent fix, it might get me another 6-12 months while i try and find someone to replace the capacitors on the original board. I thought it made sense at the time......I hope i was right :/

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NEW BOARD DIDN"T WORK
by Gojyumatt / November 7, 2009 6:48 AM PST
In reply to: No recycled board.

got the new board in on thursday and installed it in 20 min. everything started up great and picture turned on in about 3 seconds. Things seemed like they were going great until today!!! Saturday afternoon turned on the tv and AGAIN black screen with sound. Now i have a brand new power board in there!!! ANY OTHER SUGGESTIONS????

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bummer!
by gonefishin09 / November 7, 2009 10:23 AM PST
In reply to: NEW BOARD DIDN"T WORK

the fact that the new board fixed the problem, even temporarily, seems to suggest that the board is indeed the source of the problem, but why it would then fail after a couple of days is a mystery. If it was a recycled board, maybe there was some other problem with it, or maybe it wasn't repaired properly. So on that theory, you could order another power supply board, and if that works then return the first one under your 30 day warranty. The risk is that the problem is something different, in which case you could end up with two power boards and no solution, but between the bulging caps on the original board, and the temporary fix when you replaced it, I'm still thinking the power supply is very likely the issue.

What is the board model #? I searched your TV model number and came up with a couple of possibilities like BN44-00192B and BN44-00208B, each for about $50 new.
https://www.encompassparts.com/webwiz/wwiz.asp?wwizmstr=WEB.SEARCH&mres=1&mrpn=SMGLN26A330J1DXZA

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link doesn't work
by gonefishin09 / November 7, 2009 10:29 AM PST
In reply to: bummer!

sorry, just realized that link I gave you was from a secure logged in session so it won't work for other people. to get to the same place, you can just go to www.encompassparts.com and click "Guest Login" on the left menu, and then enter your TV model number LN26A330J1DXZA in the search box on the left to get a list of parts for your TV

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power board.
by Gojyumatt / November 8, 2009 12:23 AM PST
In reply to: bummer!

the one i ordered was bn44-00192b. I got it from partstore.com. i just got another tv today, but would still love to fix my samsung. i think i will return the recycled board and try another one. : /

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encompassparts
by gonefishin09 / November 8, 2009 12:42 AM PST
In reply to: power board.

if you are going to try again definitely consider that encompassparts place. I've used them twice because they had best price I could find on brand new parts. Both times I ordered in morning and they shipped same day; items were well packed, communications were good, very professional outfit.

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thank you
by Gojyumatt / November 8, 2009 12:51 AM PST
In reply to: encompassparts

i am defiantly going to try again. and will try that site if i can get a NEW board over a recycled one. Thank you. I'll keep ya up to date on how it goes. THANKS AGAIN

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It may not be the board
by rdeponio1 / June 18, 2010 7:34 AM PDT
In reply to: NEW BOARD DIDN"T WORK

We have a 46" Samsung TV that we bought in October 2008. We started in May 2010 having trouble with our set. The same problems most people were posting: clicking when turning the TV on, getting green screen with sound, having to turn the TV off and on several times before it would work properly. Then eventually, the TV taking 30-60 minutes to turn on, and ultimately, turning itself on and off repeatedly. We finally had to unplug the set to keep it turned off.

The first technician replaced the capacitor...we still had the same problem. The second technician replaced the whole board....still had the same problem...Now they tell us it is the main board. The one that draws all the power from the the power board. They said they can replace the power board, but if they do, the main board will blow it out again anyway. So, now we don't know what to do....

I hope that isn't your problem as well.

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This sounds like my problem.
by pblaymon / November 12, 2013 10:06 AM PST

I have the clicking noise for 30 to 60 minutes after turning unit on. Now, it is in a loop of turning itself off and on repeatedly. You mentioned the main board. Do you mean the main control board?

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Ouch.
by R. Proffitt Forum moderator / November 12, 2013 10:23 AM PST

When it begins to click, please remove power and get it fixed or else you may find the repair person talking about replacing a lot of boards.

I see all the usual has been covered here so please folk, unplug these before more damage is done.
Bob

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Re: This sounds like my problem.
by Samsung_HD_Tech Samsung staff / November 13, 2013 10:06 PM PST
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Thank You Thank You Thank You
by valariemartin / November 7, 2009 7:55 AM PST

Thank you so much for the information on repairing my tv. I was able to get a guy from my church to replace the capcatiors and the tv now works again.

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Capacitor replacement
by smkymtnthndr / December 18, 2009 12:25 AM PST

gonefishin09

Did replacing the capacitors alone fix the problem without replacing the power supply board?

Thank you

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yes...
by gonefishin09 / December 18, 2009 12:38 AM PST
In reply to: Capacitor replacement

yes, in my case replacing the caps was all that was required, but I could see three visibly bad capacitors so I felt pretty confident that would be the problem. If you don't see bad capacitors, then it is hard to guess whether they might be the source of your problem or not. If you are comfortable with a soldering iron, changing the caps is quick and cheap, so you don't have much to lose by trying.

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Success!! It worked
by smkymtnthndr / December 18, 2009 10:40 PM PST
In reply to: yes...

gonefishin09

Thank you for your insight. I had 2 blown caps and 3 more were bulging. I was able to find them at a local Radio Shack. Total cost of repair was under $15.00. Problem solved.

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TV failed again -- this time an inverter board....
by gonefishin09 / June 10, 2010 2:47 PM PDT

roughly nine months have passed since I started this thread, but after initial success fixing the TV by replacing capacitors, I have had it fail two more times, so I thought I would post an update.
When the first repeat-failure happened, I inspected the power supply board, and could see no sign of problems with the capacitors that I had previously replaced. But I replaced them again anyway, and still the TV wouldn't start. So I ordered a brand new power supply board, and it worked first time. So I figured my repaired power supply board must have had some other hidden problem. I stuffed it in a closet.
A couple of months passed, and then the TV failed again, with exactly the same symptoms. So I ordered a new power supply board again, but this time, the new board didn't help. So I started to hunt around for another cause of the problem, and zeroed in on the inverter boards, of which there are four. Every time I turned on the TV, there was a buzzing sound for a few seconds, and by listening closely with the back off the TV I was able to determine that the buzz was coming from the lower right board, part INV52B24A (RL). Then I had a hunch -- we've probably all seen fluorescent lights have a tough time starting when they are cold. Well it seemed to me like the inverter was trying to start the fluorescent backlight and not quite getting it going. So following my crazy hunch I grabbed a hair dryer and started to heat up the entire area around the inverter boards, thinking that if I could get the fluorescent tubes warm, they might start up. Crazy? Well, it worked! After maybe two minutes of heating, the TV started up normally. The I powered down and left the TV off overnight. The next morning, it wouldn't start up again. So again, I grabbed the hair dryer and started heating, and again, it worked after a few minutes. Interestingly though, when the TV did start, there was still quite a bit of buzzing coming from the RL inverter board, but not any of the others. Then I got really close to the board and looked at all the transformers, and was amazed to see across one of the transformer casings, exactly where the buzz was coming from, what appeared to be a light scorch mark and a tiny crack. Could this be the problem? I decided to try to replace that board, and quickly found that this part doesn't appear to be sold by Samsung as a separate part, however I found a used board on "ShopJimmy" and decided to give it a shot. Board arrived a few days later, and upon installation, the TV immediately worked, with no hair dryer, and no buzz whatsoever. I turned it off for a couple of days to make sure it was completely cold, and it powered back up without problem. Then I decided to swap out the new power supply board with my original, repaired power supply board, and that worked too.
The TV has now worked fine for two weeks with the new inverter board. It's hard to know how the the power supply capacitor problem and the inverter problem are linked... maybe the original capacitor failure caused damage to the inverter transformer. Or maybe they are completely unrelated failures that coincidentally had the same symptoms. In any event, the TV works again, at least for now.

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You solved one problem, need help with second
by hawkster23B / July 12, 2010 11:30 PM PDT

Your posts on this forum and on techreport.com were the most informative and explanatory in dealing with the capacitor problem on Samsungs. After much research, I changed out the three 10v capacitors yesterday, and the startup problem on my 46" LCD was solved. Many, many thanks to you and the others who helped a complete soldering novice make this repair for about a dollar (thanks to a friend in the video poker business with bins full of wholesale price capacitors).

But before the capacitor repair, my set developed the problem with the dark picture at startup. And unfortunately, this problem still exists after the startup/capacitor problem was solved. I haven't tried the hair dryer test, and I haven't heard any noticeable buzzing. But, as described, the picture is dark for about 5 - 10 minutes after startup, then a subtle internal click and the normal brightness returns and the set is fine again.

You mentioned the inverters. Have you or has anyone else posted pictures or videos on the testing, repair or replacement of the inverter boards? After yesterday's success, I am willing to tackle that problem as well. Especially if I can get the kind of tech assistance that these forums provided on the capacitor issue.

Thanks very much for your posts, and I'm looking forward to more education.

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