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Since this site helped me fix my own expensive TV, I thought that I'd contribute my own experience with it in case it helps someone else in some way. I owe a large debt to this forum to save me from throwing out my cherished TV!

I purchased my Samsung PN64F8500 in November 2013 along with a 5 yr extended warrantee. The place I purchased it from went out of business about 2 years later. The TV died in Sept. 2016 - it clicked while trying to power on and only infrequently would actually turn on. Once it was on, it seems to work OK.

I called the service company and they sent a tech out to look at it. He diagnosed it to a bad Y-Main board, but could NOT find a replacement anywhere. I did not like any of the other LED TVs they offered as a replacement, so I took the cash buyout and purchased a 55" LG OLED by kicking in a few hundred $ more. (I really like the OLED, but still missed the 64" plasma.) That's when I began researching into this issue and stumbled on the AVS forum. I even purchased the service manual for the TV which promised to have schematics in it (it did NOT!). :(

For a couple years, I left the TV in our enclosed porch until I finally got serious about fixing it - which came a few weeks ago. I ordered 10 of the famous caps from Mouser (thanks to other posts!) and downloaded the Samsung service bulletins that someone else posted here.

Following the service bulletin for this issue, I removed the back and proceeded to check the voltages related to the cap failures. I did not see the voltages I was supposed to and was now unsure if my TV was actually exhibiting the related failure mode that the caps are supposed to fix. Further on-line research led me to other tips and eventually I found a small connector from the power supply to the X-Main board that was not quite seated fully enough to make good contact. (The service tech apparently didn't bother to make sure the TV was restored to its original state as I requested.) With the connector fully seated, I now measured the right voltages at the key test points.

It's important to note that there are a couple voltages (VS & VSCAN) that the tech bulletin instructs you to check and they will decay slowly if the TV has an issue related to the VSCAN failure that can be fixed by replacing the three 10uF caps. As a further check, I found that disconnecting one end of the flat ribbon cable between the Y-Main and the Main board will allow these voltages to remain steady because the error signal from the Y-Main board is blocked from the Main board and it does not automatically shutdown those voltages.

Now that I was reading the proper voltages at the test points, I could verify that they decayed slowly after I reconnected the flat ribbon cable (do this with the TV unplugged!). Satisfied that I was now looking at the exact VSCAN issue in this thread, I prepared to replace the caps. I chose to leave the board installed, so I placed the TV on top of a table so I could access the caps easily while sitting comfortably. In addition to positioning a strong task light on the work area, I wore a headlamp to illuminate the area I was working. (Good lighting is very important in this type of work.)

Following the advice on this forum as well as the service bulletin, I snipped off the caps while leaving the leads as long as possible. I carefully tinned each of those leads with solder without heating the leads up too much to avoid causing connectivity issues with the solder connection to the multi-layer circuit board. I then snipped off the new caps from their carrier strips so they had about a half inch on each lead. I brushed on a small bead of solder on the lower part of these leads to prepare them for the tack solder to the old cap leads.

I tack soldered the middle cap first as suggested in the bulletin. This way, I was able to bend the cap slightly to either side as I worked on the two outside caps. I kept the soldering tip on the leads only as long as needed for the solder to melt together and hold the caps in place. My work was far from pretty, but it looked like things made a solid connection which is all that matters. After carefully inspecting my work to verify nothing was shorted and there was sufficient space between the leads and other components/pads, I plugged the TV in and heard that beautiful sing-song of the powering up sequence through the speakers!

By the time I went around to the front of the TV, it was already displaying the apps that it was updating. I did a check of the test point voltages to make sure they matched the voltages on the inside label and put the TV through its paces with audio and video tests and verifying the WiFi connection to make sure it connected to my Netflix account. Everything worked!

Note that replacing the three caps with ones of the same 10uF rating, the TV is less apt to drift from the calibrated voltages on the inside label. If the voltages do not match the ones on the label, then adjustment of the voltages is required or the TV could experience video anomalies or non-optimal picture quality. The service bulletin explains how to do this.

The TV has since replaced the LG OLED in our family room in time to watch the destruction of King's Landing in Game of Thrones. The operation was a success!

So - many thanks to members of this forum for providing the info I needed to perform this repair as well as links to service bulletins and replacement parts. If my little story helps even one person fix their own TV, then it was worth the time it took me to write it.

Thank you!
 

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Since this site helped me fix my own expensive TV, I thought that I'd contribute my own experience with it in case it helps someone else in some way. I owe a large debt to this forum to save me from throwing out my cherished TV!

I purchased my Samsung PN64F8500 in November 2013 along with a 5 yr extended warrantee. The place I purchased it from went out of business about 2 years later. The TV died in Sept. 2016 - it clicked while trying to power on and only infrequently would actually turn on. Once it was on, it seems to work OK.

I called the service company and they sent a tech out to look at it. He diagnosed it to a bad Y-Main board, but could NOT find a replacement anywhere. I did not like any of the other LED TVs they offered as a replacement, so I took the cash buyout and purchased a 55" LG OLED by kicking in a few hundred $ more. (I really like the OLED, but still missed the 64" plasma.) That's when I began researching into this issue and stumbled on the AVS forum. I even purchased the service manual for the TV which promised to have schematics in it (it did NOT!). :(

For a couple years, I left the TV in our enclosed porch until I finally got serious about fixing it - which came a few weeks ago. I ordered 10 of the famous caps from Mouser (thanks to other posts!) and downloaded the Samsung service bulletins that someone else posted here.

Following the service bulletin for this issue, I removed the back and proceeded to check the voltages related to the cap failures. I did not see the voltages I was supposed to and was now unsure if my TV was actually exhibiting the related failure mode that the caps are supposed to fix. Further on-line research led me to other tips and eventually I found a small connector from the power supply to the X-Main board that was not quite seated fully enough to make good contact. (The service tech apparently didn't bother to make sure the TV was restored to its original state as I requested.) With the connector fully seated, I now measured the right voltages at the key test points.

It's important to note that there are a couple voltages (VS & VSCAN) that the tech bulletin instructs you to check and they will decay slowly if the TV has an issue related to the VSCAN failure that can be fixed by replacing the three 10uF caps. As a further check, I found that disconnecting one end of the flat ribbon cable between the Y-Main and the Main board will allow these voltages to remain steady because the error signal from the Y-Main board is blocked from the Main board and it does not automatically shutdown those voltages.

Now that I was reading the proper voltages at the test points, I could verify that they decayed slowly after I reconnected the flat ribbon cable (do this with the TV unplugged!). Satisfied that I was now looking at the exact VSCAN issue in this thread, I prepared to replace the caps. I chose to leave the board installed, so I placed the TV on top of a table so I could access the caps easily while sitting comfortably. In addition to positioning a strong task light on the work area, I wore a headlamp to illuminate the area I was working. (Good lighting is very important in this type of work.)

Following the advice on this forum as well as the service bulletin, I snipped off the caps while leaving the leads as long as possible. I carefully tinned each of those leads with solder without heating the leads up too much to avoid causing connectivity issues with the solder connection to the multi-layer circuit board. I then snipped off the new caps from their carrier strips so they had about a half inch on each lead. I brushed on a small bead of solder on the lower part of these leads to prepare them for the tack solder to the old cap leads.

I tack soldered the middle cap first as suggested in the bulletin. This way, I was able to bend the cap slightly to either side as I worked on the two outside caps. I kept the soldering tip on the leads only as long as needed for the solder to melt together and hold the caps in place. My work was far from pretty, but it looked like things made a solid connection which is all that matters. After carefully inspecting my work to verify nothing was shorted and there was sufficient space between the leads and other components/pads, I plugged the TV in and heard that beautiful sing-song of the powering up sequence through the speakers!

By the time I went around to the front of the TV, it was already displaying the apps that it was updating. I did a check of the test point voltages to make sure they matched the voltages on the inside label and put the TV through its paces with audio and video tests and verifying the WiFi connection to make sure it connected to my Netflix account. Everything worked!

Note that replacing the three caps with ones of the same 10uF rating, the TV is less apt to drift from the calibrated voltages on the inside label. If the voltages do not match the ones on the label, then adjustment of the voltages is required or the TV could experience video anomalies or non-optimal picture quality. The service bulletin explains how to do this.

The TV has since replaced the LG OLED in our family room in time to watch the destruction of King's Landing in Game of Thrones. The operation was a success!

So - many thanks to members of this forum for providing the info I needed to perform this repair as well as links to service bulletins and replacement parts. If my little story helps even one person fix their own TV, then it was worth the time it took me to write it.

Thank you!

Thanks for the informative post.
Could you be a bit more specific about the test to diagnose if the issue is related to the 3 caps.
If I power ON the TV and measure the VS (or VSCAN ?), what exactly do you describe as a "slow decay" (sec, min ?)
 

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Thanks for the informative post.
Could you be a bit more specific about the test to diagnose if the issue is related to the 3 caps.
If I power ON the TV and measure the VS (or VSCAN ?), what exactly do you describe as a "slow decay" (sec, min ?)
The VS and VSCAN are two test points for voltage checks. They *should* remain stable, steady state voltages when the TV is working normally. When a failure is detected in the VSCAN circuitry (as I understand it), a signal is sent to the power supply to shut down those voltages. Because of the capacitive nature of the circuits, the voltage slowly drops, or decays, at that point. As you observe the voltage meter while checking these voltages, the meter will slowly indicate lower and lower voltages - approaching 0V although it would take a very long time to get there since the rate of voltage drop slows down considerably as it approaches 0. (This is just the nature of capacitive effects in circuits.)

I only monitored the voltage for a few seconds and noticed it was steadily dropping, which is all I needed to know. The voltage begins dropping immediately after trying to power ON such that I never actually read the proper voltage when I measured the test points - they were already down to about 70% of their intended voltage level and dropping quickly. After the caps were replaced, the voltage was rock steady and matched the voltage on the inside product label.

Hope that explains things better.
 

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The VS and VSCAN are two test points for voltage checks. They *should* remain stable, steady state voltages when the TV is working normally. When a failure is detected in the VSCAN circuitry (as I understand it), a signal is sent to the power supply to shut down those voltages. Because of the capacitive nature of the circuits, the voltage slowly drops, or decays, at that point. As you observe the voltage meter while checking these voltages, the meter will slowly indicate lower and lower voltages - approaching 0V although it would take a very long time to get there since the rate of voltage drop slows down considerably as it approaches 0. (This is just the nature of capacitive effects in circuits.)

I only monitored the voltage for a few seconds and noticed it was steadily dropping, which is all I needed to know. The voltage begins dropping immediately after trying to power ON such that I never actually read the proper voltage when I measured the test points - they were already down to about 70% of their intended voltage level and dropping quickly. After the caps were replaced, the voltage was rock steady and matched the voltage on the inside product label.

Hope that explains things better.
When measuring VS, I noticed the decay (VSCAN went to 0 much faster if I recall)



As you suggested, I unplugged the ribbon from the Y board to the main board.

The VS didnt drop to 0, but the signal wasn't rock steady: there was quite a bit of large oscillations in the VS voltage.


I did change the 3 blue capacitors, but my TV continued to shut down by itself (and make the clicking noise if I try to restart right away)
Some shop doing videos on how to repair TVs mentioned that all 17 of blue capacitors from the Y board should be changed since they have seen others failing as well.
I have already replaced 10 of them, but still the same problem (all other capacitors show an increase in resistance over time...sometime to infinity, sometime leveling off to a value, but different than 0)


One thing that puzzle me: when I do a resistance measurement to check the capacitors on the circuit (only to tell me if they are good or bad) without powering ON the TV, I noticed that one capacitor
gave me a 0 resistance reading. I changed it with a brand new mouser one, and still get that 0 reading.


The TV is still able to function from time to time....so I'm not sure if this can truely be THE problem. it's the blue capacitor on the bottom left corner, just below an integrated circuit.


In the past, I have chaged the power supply board (2 times) and it fixed the problem but only for 1 year or so before the problem re-appeared. That's why I'm suspecting that it's the Y board (and maybe this is deteriorating the Power supply over time)
 

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Well, about a year later and mine started shutting off the other day.

Forgot I'd touched up solder on the power supply. Needed it again. Some of the transistors didn't quite have a great connection. Also touched up one of the famous 3 capacitors legs that seemed possibly a little loose after wiggling it to check.

While I was at it, I had a couple 80mm case fans and got them mounted on the back. Case fan screws fit right through ventilation holes in the back. Sacrificed a USB cable to wire them up. Currently just using an old phone charger for power vs on board USB.

Anyway, to those with problems, it might just be a couple points on the power supply.

I'll feel better after running it for a few more hours tonight. It was shutting off after about one hour. No LED or anything. So far, it's holding steady.
 

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I did change the 3 blue capacitors, but my TV continued to shut down by itself (and make the clicking noise if I try to restart right away)


Some shop doing videos on how to repair TVs mentioned that all 17 of blue capacitors from the Y board should be changed since they have seen others failing as well.


I have already replaced 10 of them, but still the same problem (all other capacitors show an increase in resistance over time...sometime to infinity, sometime leveling off to a value, but different than 0)

QUOTE]


My understanding is that that the problem with these caps is that their temperature tolerance was below spec for the temps that this TV actually generates internally, so they eventually begin to work like dirt.


So, which caps and how many caps fail can be all over the place, depending on the usage, environment, and temperature behavior of your TV.


I fixed mine by replacing just the three notorious capacitors, but one place that I found selling ceramic capacitor replacement kits recommended replacing all of them, because they were all below the spec and could fail depending on the particulars of your TV.
 

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hello everyone guys,
unfortunately my PS64F8500 also died exactly as described by others, but the same day a vertical line appeared on the left side of the screen yellow / orange ...
I can't find capacitors in online stores in Italy or Europe, is there any Italian that can give me any indication?

Grazie.
:)
 

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Wow, add me to the list of inevitable failures. Bought my PN64F8500 from Best Buy back in Oct 2014 and the love affair finally came to a close this week. My Square Trade Warranty expired in November of last year. Soon after I found that at times the TV would freeze or lock up especially when using the standard remote control. I could however use the cable box to change channels, but I had to use the back TV Controller to adjust sound. Unplugging TV and letting it sit would reset it allowing standard remote use until it seemed to get to a certain temperature and it would freeze up again. Always had a red LED once reset, but it never blinked. No issues of no picture, but sound or clicking from the TV. This week its just dead with no red LED, picture, or sound. I assume its a bad power board, so I'm going to replace with a supposed working used part. Next, I will try to assess if the 3 Y-Sus board capacitors are bad and try to replace. Don't know if it might have led to the power boards failure (assumption). Need to try to get TV on life support until new Panasonic GZ2000 is available. I checked and the TDK capacitors aren't available, so what do others suggest as an alternative?
 

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This, in USA, search in Mouser:

810-FA20X7S1H10600

and

810-FA20X7S1H106KRU6

ps
I can't insert links:

To be able to post links or images your post count must be 5 or greater. You currently have 2 posts.
Thanks a bunch, ouragan66. Got my used power supply board today, so I'm just going to order the capacitors now and replace everything at once. The link for others for the alternative capacitors is: https://www.mouser.com/ProductDetail/TDK/FA20X7S1H106KRU06?qs=/ha2pyFadujcyOxVJ1%2BOCPw8otOVEd0CzQLn8QUpsLUShMNMNCRqDNdiy44VI0kV
:)
 

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Thanks a bunch, ouragan66. Got my used power supply board today, so I'm just going to order the capacitors now and replace everything at once. The link for others for the alternative capacitors is:
:)
Not at all!
today I have disassembled my 64 ", unfortunately I don't see well,and for me cutting the capacitors and soldering in the stems the new ones is impossible.
 

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Not at all!
today I have disassembled my 64 ", unfortunately I don't see well,and for me cutting the capacitors and soldering in the stems the new ones is impossible.
Maybe use the strongest light you have to illuminate the area (lampshade off) or have someone hold a bright flashlight on the spot until you can complete solder.
 

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Maybe use the strongest light you have to illuminate the area (lampshade off) or have someone hold a bright flashlight on the spot until you can complete solder.
I tried glasses+light+lens but I just can't see the stems to cut!
Unfortunately, the illness I have had in recent years has definitely worsened my vision.
 

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I believe it involves the temperature required to de-solder and risk of burning or damaging (burning) the circuit board.
I have a Weller soldering station with temperature control.
the printed circuit board has three layers, maybe the capacitor is connected to all 3 layers?
 

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Not at all!
today I have disassembled my 64 ", unfortunately I don't see well,and for me cutting the capacitors and soldering in the stems the new ones is impossible.
I don't have the manual dexterity to do this soldering job, so when I fixed my 64F8500 I removed the board and took the board and capacitors to a local electronic repair guy. He did it while I waited for $50.


Why can't they simply be unsoldered?
Why is the electronic card triple?

It's a multi-layer board. My local guy was originally going to unsolder the caps, even when I showed him the Samsung service bulleting that told the techs to clip off the caps and tack-solder the new caps to the old wires. Then he began handling the board, and went "Ohhhhhh, this has a few layers I'd need to get the wires loose from", and then he clipped off the old caps.
 

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I managed to cut the capacitors, unfortunately one had a very short leg ...

I think I'll combine all three of them and I will make a single weld on the longer legs on the board.
Yes I read the Samsung notes, in fact I decided to cut.













 
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