Panasonic P50G20E

[bluebear]

Hi
I'm having a weird problem with my Panasonic P50G20E.
After a few minutes the screen starts "scrolling" vertically, or broken up in different sections. Hard to explain, see picture. Power off with switch on TV, temporary cures the problem, then it starts again.
Nothing seems to change when using the remote. Eg. menu changes. The image is locked in this scrolling mode.
Anyone had this problem?
It is not shutting down and no blinking errors.
Updated firmware, but still the same. Any advise is appreciated.

[tw2005]

Re: Panasonic P50G20E

I'd say your A-board has suffered heatstroke on one of the BGA chips and the solders have come free.

When looking pay attention to what version , each size has a different revision.

[tw2005]

Re: Panasonic P50G20E

What's with the word Super Resolution being displayed on the left? Is that from the TV?

[bluebear]

Re: Panasonic P50G20E

What's with the word Super Resolution being displayed on the left? Is that from the TV?

Thanks for your answer, yes its from the menu. At this point I had it unplugged from any source.
That was my assumption too, something with the AD board, hence I hoped for a firmware upgrade. Anything to do, or is a board swap the best option at this point?
Added some board pictures.

[tw2005]

Re: Panasonic P50G20E

Board unless you know or have a bga rework station. They very hot those chips even with a heatsink.

[ReeceyBurger123]

Re: Panasonic P50G20E

Probably the chips with no heatsink that have failed.

[bluebear]

Re: Panasonic P50G20E

Thanks, maybe a later rework then.

Its not that easy find an A-board for this.
The TXN/A1MFUE on the board I guess is a revision number?
Are these boards interchangeable among the different model numbers?

[tw2005]

Re: Panasonic P50G20E

I know a few tricks. If stuck for revision you can find a board for smaller model and do eeprom swap

[bluebear]

Re: Panasonic P50G20E

I know a few tricks. If stuck for revision you can find a board for smaller model and do eeprom swap

Could be an option, though would a different revision work. Seems there are many P50G20B boards for reasonable prices. Not sure what are the differences, seems though that they are not compatible.

[bluebear]

Re: Panasonic P50G20E

Would it be any use going at them with a handheld hotair, model cheap?

[tw2005]

Re: Panasonic P50G20E

Would it be any use going at them with a handheld hotair, model cheap?

May give a temporary result or help narrow which chip.

[tw2005]

Re: Panasonic P50G20E

On the under side of this board , there's a large Hynix Flash chip, 48 pin ic8921, if there is a white sticker on it, what's the 3 digts 2 letters?

[bluebear]

Re: Panasonic P50G20E

Ok i Will Hook it off. Aything to consider before unhooking, so I dont damage other parts?

[Hombre]

Re: Panasonic P50G20E

Maybe to change termal pad between cpu and heatsink, or if it is a paste to change it, and then install a fan on heatsink, maybe it would help, for how long i don't know, but just an idea

[bluebear]

Re: Panasonic P50G20E

Maybe to change termal pad between cpu and heatsink, or if it is a paste to change it, and then install a fan on heatsink, maybe it would help, for how long i don't know, but just an idea

Hombre, you are a genius. Had some time to continue testing this evening. Measured the chips and the little one on the a-board where hot to touch. Measured 90 degrees Celsius with my IR thermometer. Tried first with my wife's hair blower with no heating and it worked longer than ever before. Mounted som small DRAM heatsinks if that would help. Nope still to varm.
Then tried a small fan, and voila. It has now stayed on for 1 hour.
Lovely, maybe a short fix we will see. I mounted the fan on the outside of the backpanel and power it by a separate power supply. A little noisy though, have to try if less voltage will be enough to cool the chip. Great idea though, thanks Hombre. Also thanks to ReeceyBurger123 and tw2005 , I´m still interested in your solution, picture attached if this does not work as planed.
The white sticker has 329AK on it.

[tw2005]

Re: Panasonic P50G20E

I 'll check tonight that chip. I think the b version software is different like 921?

[bluebear]

Re: Panasonic P50G20E

Short update.
Still having the same problem, but now it runs for hour, rather than minutes.
Perhaps I need to increase the fans to keep it cool enough.
tw2005, did you find anything of the P50G20B board?

[tw2005]

Re: Panasonic P50G20E

Short update.
Still having the same problem, but now it runs for hour, rather than minutes.
Perhaps I need to increase the fans to keep it cool enough.
tw2005, did you find anything of the P50G20B board?

No , not really. can't find a manual for it. But SJ had them quite cheap so if you can handle desoldering and soldering that hynix chip 48pin, the rest are easy.

I was looking at the 50S20B manual and it has 329 version on ic8921 but the image in SJ shows 921 on the G20B board.

Somone else did a board swap from UK to Europe but needed some mods due to fans missing and the board was tripping because it came from a fanned model.

https://www.badcaps.net/forum/showthread.php?t=24745

Maybe send a PM may get some ideas.

[bluebear]

Re: Panasonic P50G20E

Thank you tw2005, I've seen that thread before.

So basically, it would be possible to swap the HYNIX chip from my P50G20E board to a P50G20B board. That would eliminate the fan problem I assume.
Or just resistor mod the fan connectors and be done with it.

[Alastair E]

Re: Panasonic P50G20E

Cant fool it with a resistor....

Fan has tacho-generator that supplies mainboard with square-wave depending on speed. no square-wave, it shuts down....