Panasonic TX-P42GT20E 3D , does not turn on!

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

50v20e, not 100% sure if 42" has but if it's 11 blinking then whatever it's out of did.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

It was STANISLAV, trying to fix a 50G20E, used 50V20B mainboard and pretty sure the main from the V20B and V20E are the same. He ran into the 11 blinks and if you read that post I'm pretty he came up with a workaround if you decide to permanently make this a 2D TV

https://www.badcaps.net/forum/showth...ht=v20e&page=3

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Oh , which V20E (size) is that board from?

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

The R8747 from the V20E mainboard is also gone. ( Happened when i removed the IC ).

So just to make sure you understand ( My english is not the best ).

The mainboard from V20E without the R8747 & IC8701 works perfectly.
Im still thinking its the D board as you said it can also turn on the tv.

The mainboard from V20E without the R8747 & IC8701 works perfectly. It would because that part is not monitored for failure except if a voltage was shorted

Well , I admire the fact you're backing yourself, but i can't agree.

When you plug in, do relays click, front LED on for standby? If not the A board is toast. You have a fried IC on that A board, it's like a smoking gun and most likely lightning came through the antenna system.

It's happened to me but just lost a HDMI luckily because the antenna came via a set top box then the box via HDMI, other wise i dare say my A board would have cooked too.

Anyway it's all academic now, wait and see.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Aah dont worry about the timezone , im not in a hurry! Im already glad that your helping me out.
If you have any suggestions to fix the mainboard just let me know! Ordered the D board from the UK so it will take 2/3 days..... ( was only 25 euro's ).

Are you 100% sure that the V20E has fans?

Fairly sure. the V20A (Australia) V20Z(new Zealand) G20,G25 (USA) do not but I have this memory the V20e does as i think someone else used a different board to fix theirs and had 11 blink issue no fans, may have been Hombre?

i'll check it out

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

The R8747 from the V20E mainboard is also gone. ( Happened when i removed the IC ).

So just to make sure you understand ( My english is not the best ).

The mainboard from V20E without the R8747 & IC8701 works perfectly.
Im still thinking its the D board as you said it can also turn on the tv.

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Aah dont worry about the timezone , im not in a hurry! Im already glad that your helping me out.
If you have any suggestions to fix the mainboard just let me know! Ordered the D board from the UK so it will take 2/3 days..... ( was only 25 euro's ).

Are you 100% sure that the V20E has fans?

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Yes the 8 pin device on the picture is blown. On the picture you can see 2 components with 8 legged pins. One on the left and on the right. Im talking about the device above the black card reader.

I took the same device from the V20E mainboard but still same issue! Also the V20E mainboard without the blown device works perfectly so it probably is just for the USB only......

yeah, i think I got it. would have to back trace where it goes to see what else is taken out, might be in the too hard basket.

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Yes the 8 pin device on the picture is blown. On the picture you can see 2 components with 8 legged pins. One on the left and on the right. Im talking about the device above the black card reader.

I took the same device from the V20E mainboard but still same issue! Also the V20E mainboard without the blown device works perfectly so it probably is just for the USB only......

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Its also a 8 legged component

You saying the blown part is the 8 pin device? Time zones make it hard, be 1230am when you finish and if you stay up til 10pm that's 530am here.

I'm looking at that IC because it has 5 and 3.3v going to it and is used for the USb so if that is shorted that would stop the A board from running or at least suspect.

A couple of guys have ressurected their A boards from lightning via the HDMI ports which took out some devices and shorted the 3.3v I think, so that's a theory anyway. I'm sure you can live without USB if that's all that's doing it.

It's a nice challenge anyway to see if it can be brought back from the dead

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Its also a 8 legged component

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

This is the best that i can do atm.
Its 11.30 in the morning and im.working till 5....
The blown part is on the right side next to the usb.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

I will check that when im home.
I dont know if there was a device connected , i bought it with the knowledge " tv does not turn on due to lightning".

I will make some clear pictures of the board.

what time is it there?

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

I will check that when im home.
I dont know if there was a device connected , i bought it with the knowledge " tv does not turn on due to lightning".

I will make some clear pictures of the board.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

something a little random, is ic8701 near the burnt area? 8 pin device.

can you measure resistance between pins 1-2,1-5, 1-8

was anything connected in that port when the lightning hit?

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Hope this is the same board TNPH0898

actually I have 2 shots of the board print, i had the wrong spot.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Im also thinking your right TW2005 , im still learning!

Its probably the cpu on the mainboard? But why does it turn on without the D board?

This is what I'm trying to say, it is the D board turning the TV on. the guide is on it's way . Normally the A board does but it states that

"Note: The PANEL-MAIN-ON command (3.2V) from the D board can also trigger the relays, but since it's preceded by TV-SUB-ON, it has not effect on the relays because by
the time this command is output, the relays are already energized."

disconnect d25 and you should find that the TV does not turn on even with the LVDS removed

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Im also thinking your right TW2005 , im still learning!

Is it the cpu on the mainboard? But why does it turn on without the D board?
Or is it a short somewhere?

[Moreno83]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Not sure if its a diode or ic , it does have that part number on it. Its viscible on the mainboard picture , in the upper right corner.

[tw2005]

Re: Panasonic TX-P42GT20E 3D , does not turn on!

Im talking about both boards.
At first i used the mainboard from the VT20E without the LVDS cable and it turns on.
Then i used the original mainboard from the GT and it also turned on without the LVDS cable and this board had a blown diode.
I removed the diode from the VT20E board and placed it on the GT board but fault is still the same.

Ok, so all that proves is the TV will turn on with the LVDS lead disconnected and produce a white screen which is correct operation of the D board.

the A board is not turning the panel on when connected.

You'll confirm for sure once you have the replacement D board but I'm confident I'm right but either way if it fixes it then great , I don't have a problem being wrong and learning but that's my gut feeling with this one.

I'll upload the 3 d manual for you as it describes the operation at turn on.