Panasonic 65fx700b intermittent tcon problem

[Michaelrobbo]

Bought the TV about a month ago faulty as it would take about an hour to turn on turns out it was the tcon board as with a reflow has been working great for a month but now the problem is returning upon looking for a replacement there are none on the Internet looked everywhere the only board I can find close is for a 55fx700b which has the same sub model which is a 6870C-0757A but a different main part number mine is a 6871L-5491A and the one for the 55fx700b is a 6871l-5478h anyone had any joy in swapping theses or repaired the original board any help would be appreciated

[diif]

Re: Panasonic 65fx700b intermittent tcon problem

If a reflow fixed the tcon for a month, reballing it should fix it permanently.

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Do you know anyone in the UK that could do it and how much? Reakon I'd do any damage swapping the tco. With the 55 inch model maybe if I swapped the epprom chip over of the old one if all the other parts match uo

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Finally managed to sort this if anyone has the same problem you order a tcon for the 55fx700b 6871l-5478a and your remove 2 sets of caps from the board will put the numbers up tomorrow then use a ch341 programmer to read the epprom of the previous 5491a board and flash it to the new board or just do a chip swap with 24a32 epprom on the board. Now the TV runs great known issues with this model of TV and the tcons are near impossible to get hold of

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Heres a picture on what it would do after the TV would warm up you then turned it off and on and then it would work this will fix this problem models also effected are 65fxw724

[nomoresonys]

Re: Panasonic 65fx700b intermittent tcon problem

Nice fix, glad you didn't waste money on a reball, thanks for followup.

[nomoresonys]

Re: Panasonic 65fx700b intermittent tcon problem

For those that think a reball is always the answer AND don't presume to tell me you know MORE than Louis Rossman: https://www.youtube.com/watch?v=1AcEt073Uds

[diif]

Re: Panasonic 65fx700b intermittent tcon problem

For those that think a reball is always the answer AND don't presume to tell me you know MORE than Louis Rossman: https://www.youtube.com/watch?v=1AcEt073Uds

There's a very big difference between faulty Nvidia chips and a failed/cracked bga.

[nomoresonys]

Re: Panasonic 65fx700b intermittent tcon problem

You are WEAK, as is your arguments, It is a very good thing that you did not become a defense attorney, they are bga chips, the end.

[diif]

Re: Panasonic 65fx700b intermittent tcon problem

You are WEAK, as is your arguments, It is a very good thing that you did not become a defense attorney, they are bga chips, the end.

I didn't think you would understand the difference. The Nvidia chips he talks about were from a specific time and suffered from faulty engineering, he is totally correct in that respect, "Bumpgate" is well documented.

As far as I am aware he doesn't repair TVs or consoles that have all suffered from cracked solder joints of the BGAs due to repeated thermal cycling or from tin whiskers causing a short. Occasionally the chips do die, probably from heat but the majority have been fixed with reflowing or reballing.

[nomoresonys]

Re: Panasonic 65fx700b intermittent tcon problem

It's not Nvidia chips exclusively BUT I didn't think you would grasp that EITHER and they die a lot more than occasionally, that's why reballing and reflows are not working per your bad advise in this case, which the chip wasn't even the problem.

[diif]

Re: Panasonic 65fx700b intermittent tcon problem

It's not Nvidia chips exclusively BUT I didn't think you would grasp that EITHER and they die a lot more than occasionally, that's why reballing and reflows are not working per your bad advise in this case, which the chip wasn't even the problem.

My experience of reflowing and reballing is clearly much much larger than yours and yes, Louis is talking exclusively about nvidia chips and why it's pointless reflowing/reballing those. He has little experience with consoles or TVs, which definitely do benefit from reflows/reballing. And from personal experience I can say that the BGAs fail far more then the chips.
I'm not sure how you can clam it wasn't even the problem in this case, OP did a reflow that lasted a short while, I'm guessing it wasn't a very good one (no offence OP).

[nomoresonys]

Re: Panasonic 65fx700b intermittent tcon problem

If you had average reading comprehension dif, then you would have gathered that it was an eeprom problem that the OP solved.

[SMDFlea]

Re: Panasonic 65fx700b intermittent tcon problem

If you had average reading comprehension dif, then you would have gathered that it was an eeprom problem that the OP solved.

You can both agree to disagree. Leave it at that !!!!!!!

[Topcat]

Re: Panasonic 65fx700b intermittent tcon problem

You can both agree to disagree. Leave it at that !!!!!!!

I'm onboard with this theory....a tech disagreement is one thing, but when it sinks to personal level & name calling, its time to knock it off.

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Can confirm the problem was with the dc-dc ic part number sw50212 but couldn't source one it would only work when heated so was failing not the solder so to fix I got a working board off a 55inch and did an epprom swap and removed some capacitors hope this helps people with the same problem

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Caps to removes are c410 to c419 and c400 to c409

[Michaelrobbo]

Re: Panasonic 65fx700b intermittent tcon problem

Got a copy of the 65inch tcon epprom if any one needs it

[Borics]

Re: Panasonic 65fx700b intermittent tcon problem

resolder U1, known problem with panasonic

[GCM]

Re: Panasonic 65fx700b intermittent tcon problem

Got a copy of the 65inch tcon epprom if any one needs it

Hi,
I'm looking for the Panasonic Tcon board 6871l-5491a.
I would be glad if you could help me with one .

Regards