Panasonic th-p50v20a fhd plasma-4 blinks

[tw2005]

keep the old SC board intact, they are rebuildable. Rev AF,AP,AW will work. Good luck.

[guilhermoadib]

Hi,

I googled your Thread. I own a P50V20B with a faulty SC board. Very useful info! Thank you!

I bought this TV long time ago and it was up and running as my daily driver. But, one day, heard a blow when turning it off. Next time I've tried to turn it on, it gave me 4 blinks SOS.

Taked some measures on PSU and found that VSUS was shorted. Removed SC board and VSUS measured ok again.

Ordered a SC Board (TNPA5081), suposedly from a smashed screen TV. New board is revision AF, same as my old one. Now panel turns on (black image, little light) for half a second them SOS 6.

Using your infos, I've removed SC20 and C10, and faulty went to SOS 8, so, I guess that, like you, I've got another faulty SC Board.

Them I've looked for the green led D583 on the new board and, amazingly, it is visual blowed! D583 on original board appears OK (I have pictures).

Well, it was getting late and I went sleeping. Pretend to resume today.

My plan is to ground SOS6 from pin 21 of SC20 and see if can get the TV running. Them, considering your notes, take measures from D583. If I'm lucky enough, I will just swap LEDs from original to new board.

But, I'm not very confident with bypasing SOS 6.. I'm afraid ending up with a shorted panel, mainly 'cause there isn't any more good plasma avaiable. OLED costs a ton here in Brazil, and I really never liked any LCD/LED. So, I would be really thankfull if you have any more advice on the matter, like, some measures I could take before bypassing SOS 6, just to make things less risky.. Unless you consider that it is safe enough to just ground SOS 6 and check D583 straight away

Thank you! Best reggards, and sorry for my english.

[tw2005]

Hi,

I googled your Thread. I own a P50V20B with a faulty SC board. Very useful info! Thank you!

I bought this TV long time ago and it was up and running as my daily driver. But, one day, heard a blow when turning it off. Next time I've tried to turn it on, it gave me 4 blinks SOS.

Taked some measures on PSU and found that VSUS was shorted. Removed SC board and VSUS measured ok again.

Ordered a SC Board (TNPA5081), suposedly from a smashed screen TV. New board is revision AF, same as my old one. Now panel turns on (black image, little light) for half a second them SOS 6.

Using your infos, I've removed SC20 and C10, and faulty went to SOS 8, so, I guess that, like you, I've got another faulty SC Board.

Them I've looked for the green led D583 on the new board and, amazingly, it is visual blowed! D583 on original board appears OK (I have pictures).

Well, it was getting late and I went sleeping. Pretend to resume today.

My plan is to ground SOS6 from pin 21 of SC20 and see if can get the TV running. Them, considering your notes, take measures from D583. If I'm lucky enough, I will just swap LEDs from original to new board.

But, I'm not very confident with bypasing SOS 6.. I'm afraid ending up with a shorted panel, mainly 'cause there isn't any more good plasma avaiable. OLED costs a ton here in Brazil, and I really never liked any LCD/LED. So, I would be really thankfull if you have any more advice on the matter, like, some measures I could take before bypassing SOS 6, just to make things less risky.. Unless you consider that it is safe enough to just ground SOS 6 and check D583 straight away

Thank you! Best reggards, and sorry for my english.

I would not earth out the SOS6 line in case the LED is not blown and the board is bad. I've gotten away with it once. On 2 other occasions I burnt a hole in the board and shorted out both sd/su boards.

You should be able to prove the LED good or not with just a meter on diode. If it is open that will trip SOS6. If anything I'd bridge it, or find any small led even a normal 3mm leaded one and put it in cct. The LED in that baord is very tiny and don't be surprised if it gets destroyed trying to remove it.

Or , return the board

[guilhermoadib]

I would not earth out the SOS6 line in case the LED is not blown and the board is bad. I've gotten away with it once. On 2 other occasions I burnt a hole in the board and shorted out both sd/su boards.

You should be able to prove the LED good or not with just a meter on diode. If it is open that will trip SOS6. If anything I'd bridge it, or find any small led even a normal 3mm leaded one and put it in cct. The LED in that baord is very tiny and don't be surprised if it gets destroyed trying to remove it.

Or , return the board

LED is 100% blown on new board, already tested. LED on the original board is good.

Thinking about this, I will just try to measure LED anode and cathode on power up (like I've said, the panel switchs on for half a second, them SOS 6). If I got good measures, I will just bridge LED, or put another one, like you said.

Thanks for replying! I will post results.

[guilhermoadib]

Moving on, I've measured LED anode and cathode on power up. Cathode gave me 0V and anode gave me 143V rise, them TV shuts down with SOS 6. Measured 3 times, and TV always shut down on 143V.

LED is open, so it's triggering SOS 6.

Reading again post n# 17, I realized that SOS 6 would trigger at 151V, even if LED is bridged. So I temp bridged LED, TV turned on, no SOS 6, let it run for a minute. Couldn't verify picture, because it was laid panel down on my desk (didnt't have nothing better to bridge than a small angled scissor, that I needed to press a little).

Aparently, VMID is ok, since it's not triggering SOS 6 with bridge, so I will just try luck, solder another LED and see if I can get the TV up and running.

Any more suggestions?

Update:
Checked image on tuner, working correctly, menus too!

[guilhermoadib]

Finally, tried swapping LEDs, but the good LED burned when I've tried to remove.

Didn't have any other LED around, so I've bridged D583 with a small cap leg. Closed everything and TV is in perfect shape again. Image even seens to got improved (maybe the other SC board wasn't that good for some time). I've already used it for ~10h before that, everything is ok.

I guess light strokes twice here. Same problem. Maybe this LED just burns when panel breaks, and sellers just don't test boards after that.

Do you think it's a problem to just let this LED bridged? Suposing SOS 6 will ocur if VMID rises above 151V, I'm not very concerned.. But, again, if current rises, the bridge will propably not blown.

Thank you for all the help!

[tw2005]

Finally, tried swapping LEDs, but the good LED burned when I've tried to remove.

Didn't have any other LED around, so I've bridged D583 with a small cap leg. Closed everything and TV is in perfect shape again. Image even seens to got improved (maybe the other SC board wasn't that good for some time). I've already used it for ~10h before that, everything is ok.

I guess light strokes twice here. Same problem. Maybe this LED just burns when panel breaks, and sellers just don't test boards after that.

Do you think it's a problem to just let this LED bridged? Suposing SOS 6 will ocur if VMID rises above 151V, I'm not very concerned.. But, again, if current rises, the bridge will propably not blown.

Thank you for all the help!

I don't know. No, that LED does not normally present a problem. Apart from myself , your the first person to report it since me.

I'd try and come up with something to put there. In the end I used a larger surface mounted LED off a dead laptop mother board. I am surprised you get 143V, I got what I had in that drawing about 107Volts DC

[amancini]

Tudo bem, tenho uma P50v20 e procurando sobre o problema dela, ela pisca 4 vezes, achei suas postagens e vi que você é de Osório, RS, moro em Alegrete. Voce conseguiu arrumar ela? Tem como entrar em contato contigo para esclarecer o problema e como consertar? Essa tv é muito boa, não quero perdê-la. Até mais.

[mtv]

amancini,

Austech as the name suggests, is an Australian website.

All posts should be made in English, please.

[tw2005]

Tudo bem, tenho uma P50v20 e procurando sobre o problema dela, ela pisca 4 vezes, achei suas postagens e vi que você é de Osório, RS, moro em Alegrete. Voce conseguiu arrumar ela? Tem como entrar em contato contigo para esclarecer o problema e como consertar? Essa tv é muito boa, não quero perdê-la. Até mais.

Translated.

Okay , I have a P50v20 and looking about her problem , she flashes 4 times , I found your posts and see that you are from Osório , RS, live in Alegrete . You could fix it ? Its contact to clarify the problem and how to fix ? This TV is very good, I do not want to miss it. See you.


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Sounds like a typically shorted TNPA5081 SC board.

It's possible to rebuild these but it's a bit of work and not always straight forward and not a beginners job soldering either .

Q661,Q701,Q702,Q818, IC771, IC773, Q402,403, Q621,622, Q421,422, Q452, D482,D451, IC521.

Have also seen PC461, IC724, Q521,551, R421,422 damaged too occassionally

TNPA5081 Revision AF,AP or AW would work if you can find one cheap enough

[É possível reconstruir esses , mas é um pouco de trabalho e nem sempre para a frente e não um iniciantes solda trabalho também.

Q661 , Q701 , Q702 , Q818 , IC771 , IC773 , Q402,403 , Q621,622 , Q421,422 , Q452 , D482 , D451 , IC521 .

Também têm visto PC461 , IC724 , Q521,551 , R421,422 danificado também ocasionalmente

TNPA5081 Revisão AF , AP ou AW iria funcionar se você pode encontrar um barato o suficiente]

[amancini]

I apologise because i have abused the rules of the forum. I confess that i forgot this. I remembered this at home. I found this user and i want to contact him. It's very difficult to find a good professional (competent and honest) here. This will not happen again.

[mtv]

I apologise because i have abused the rules of the forum. I confess that i forgot this. I remembered this at home. I found this user and i want to contact him. It's very difficult to find a good professional (competent and honest) here. This will not happen again.

No problem.

Welcome to the forum.

[guilhermoadib]

Tudo bem, tenho uma P50v20 e procurando sobre o problema dela, ela pisca 4 vezes, achei suas postagens e vi que você é de Osório, RS, moro em Alegrete. Voce conseguiu arrumar ela? Tem como entrar em contato contigo para esclarecer o problema e como consertar? Essa tv é muito boa, não quero perdê-la. Até mais.

amancini, like tw2005 said, you probably got a shorted SC Board (TNPA5081), but the problem might be another board, or even the panel.

In my case, I've isolated the problem to the SC Board using the P50VT20 service manual (didn't found P50V20 service manual), them looked for a replacement board. I found just one in Mercado Livre, for R$ 350,00. Currently, there isn't any TNPA5081 board to sell in Brazil, considering Mercado Livre and OLX.

Like tw2005 said, your board can be repaired, but it is no easy task. The oficial Panasonic repair kit for SC Boards cost a lot here in Brazil (R$ 500,00), and the repair service with 3 months of warranty costs R$ 490,00 in Panasul, here in Porto Alegre. So, you're looking at a R$ 990,00 repair.

The other solution is buy a replacement board on ebay. They aren't cheap, and you probably will be taxed on arrival. There is a risk that the new board is damaged too, like tw2005's and mine.

So, in my opinion, if you are not a beginner and got the time, certify that the problem is the SC board and look for a replacement board online. If it's not the case, take your TV to Panasul, they are one of the two 3 stars Panasonic service center here in Brazil, and can probably fix anything in your TV, besides a damaged panel.

Considering the only model of TV currently selling here in Brazil that matchs P50V20 performance is that LG OLED, selling currently for R$ 7.000,00, R$ 990,00 to repair your TV is actually very viable.

Ps.: if I couldn't fix my TV myself, I would have accepted their price (R$ 990,00).

Ps2.: look for me on facebook, Guilhermo Adib.

[Allanhurst73]

Trying to follow this through with my dead screen is proving difficult. I purchased a replacement power board prior to finding this forum, which is why I'm here as I have refitted the original and done a bit more testing. I have four flashes of the led when powered up if I remove power to the ss board and repower there is no change if I repower after isolation of the sc board I get 7 flashes. Where is my next point to test?

Cheers

[tw2005]

Trying to follow this through with my dead screen is proving difficult. I purchased a replacement power board prior to finding this forum, which is why I'm here as I have refitted the original and done a bit more testing. I have four flashes of the led when powered up if I remove power to the ss board and repower there is no change if I repower after isolation of the sc board I get 7 flashes. Where is my next point to test?

Cheers

I'm fairly confident all the info in this thread should tell you and the fact you had a change with the SC that

A. The SC is shorted
B. You check the sd and su boards are not shorted, then if ok
C. replace / repair the SC
D. If you're really stuck and want to fix it PM me.