Panasonic tc-p55gt30

[Malachi]

Re: Panasonic tc-p55gt30

Here is a picture of the back.

[Malachi]

Re: Panasonic tc-p55gt30

All the boards and parts are exactly the same excep the vt30 seems to have a subwoofer in the back, the black speaker in the middle, that runs to a connection on the mainboard.
The two main boards have two different model numbers but I suspect the difference may be he subwoofer connection?
Tomorrow I may try the mainboard from the working gt30 in the vt30. According to the service manual, it looks like the mainboard is the problem.
Tired of messing with it tonight.
I had purchased an sc board because I only had 1 between the 2 TV but when it arrived today it was for a tc-p50st30.
Completely different. So I'll have to exchange it.

[Moreno83]

Re: Panasonic tc-p55gt30

Funny how the led stays red. My exact same tv shows a green led when its on.

Can you get the tv to display a picture? Like the menu? If the connections are the same you can also try the mainboard from the GT. Most of the times its almost the same but misses a extra hdmi/usb etc. If all connections are the same it will 90% work.

[Moreno83]

Re: Panasonic tc-p55gt30

It's a learning process but its fun. Don't forget you traded a "cheap" lcd for a good looking expensive GT30!!! If you sell it you will double/triple your money.

I would not sell it unless you can get a VT50 or VT60. Panasonic stopped making plasma's after the VT60 so its a wanted tv that you have.....

[Malachi]

Re: Panasonic tc-p55gt30

I'd prefer to get them both working and keep both and sell my 2 lg plasma tv's.
If I have to sell one of the panasonics, I'd rather keep the vt30.
I got the gt30 for the free 37" I fixed but it had no sc board. The sc board canoe out of the vt30 that I paid $150 for plus it was shorted, so $80 to fix it. So far it's cost me $260 to get 1 gt30 working. Not so cheap.

[Malachi]

Re: Panasonic tc-p55gt30

I couldn't wait till tomorrow. I would not have been able to sleep. The main board from the gt30 in the vt30, no difference.
So it must be something else.
I just checked the sd board again and now there is a short. Shouldn't part of the screen have a picture then? Or would it affect the whole thing?

[tw2005]

Re: Panasonic tc-p55gt30

I couldn't wait till tomorrow. I would not have been able to sleep. The main board from the gt30 in the vt30, no difference.
So it must be something else.
I just checked the sd board again and now there is a short. Shouldn't part of the screen have a picture then? Or would it affect the whole thing?

I was going to suggest bad buffers , it appears the upper portion has some panel activity and lower half is black.

Somewhat surprising no error blink.

[Moreno83]

Re: Panasonic tc-p55gt30

Did you also transfer the bufferboards from the GT to the VT? Looks like bad buffer board on the VT. Can you get any picture at all or just the black bars only?

[Malachi]

Re: Panasonic tc-p55gt30

Did you also transfer the bufferboards from the GT to the VT? Looks like bad buffer board on the VT. Can you get any picture at all or just the black bars only?

No picture at all. Just as the picture shows.
After he struggle i had reseating the ribbon cables, I didn't want to take them off the working TV to try it on the other.
I'll just buy one.

[Moreno83]

Re: Panasonic tc-p55gt30

Ok , that might fix the tv. You can fix the SC board yourself if you can solder

[Malachi]

Re: Panasonic tc-p55gt30

There is no sc board. The one I have works.
The SD board is faulty but I'm not skilled enough to repair it. So I'll have to send it out for repair or buy a used working one.
Would mine repaired be better than a used one that may not be repaired?
A repaired one may last longer because of better components used in the repar?

[Malachi]

Re: Panasonic tc-p55gt30

So I took the mainboard out of the non working p55vt30 and put it in the working p55gt30.
3/4 of the left screen worked. I could access the menus, ods and make changes.
The right 1/4 of the screen didn't work.
I checked the sd board again as tw2005 instructed and no beeps with meter in diode mode.

So I don't know if I have a bad A board and/or SD board.
I'm getting tired of messing with it.
A used A board is $120 plus shipping, $80 for an SD board, I have to find an SC board and I paid $150 for the TV.
Starting to not seem worth it. Maybe I should give up on the 55vt30.

[Moreno83]

Re: Panasonic tc-p55gt30

Hmm , it can be that the VT30 mainboard does not work in the GT30 , don't know how that works with firmware/service menu settings etc. It can be a defective mainboard , im not sure.

So if you put the GT30 mainboard back in , the picture is fine. Right?

You could try and use the bufferboards from the VT50 into the GT30 to see if it works. If so , then you can rule them out. It takes a bit of work but its worth the try!

[Malachi]

Re: Panasonic tc-p55gt30

Put the gt30 main board back in, all is fine. I think I'm going to order a main board.
Following the chart in the service manual indicates the main board is bad.

[Malachi]

Re: Panasonic tc-p55gt30

I think I'm giving up on this tc-p55vt30.
I got a new A board and today I new SD board but it didn't seem to solve the problem.
The bottom of the screen which previously was all black now has bands of lighter black but still not working.
So I guess I'll return the A board and SD board and be done with it.
I might keep the SD board to use if the one in the p55gt30 goes bad.
In a few years it might be harder to find.

[Malachi]

Re: Panasonic tc-p55gt30

I have taken every board out of the p55vt30 except for the 2 power supply boards and the bottom C boards and put them in the p55gt30 and they all work.
Even the A board and the subwoofer.
I don't know if that means that the TV is now a p55vt30 or if the panel itself is somehow better on the p55vt30.
The panel numbers are lightly different.
The p55gt30 is MC140FJ1431 and the p55vt30 is MC140FJ1443.
The bezel in the front is different.
The p55gt30 has a plastic bezel and the p55vt30 doesn't.

I'm thinking since the boards work in the gt30 that somehow the vt30 panel is bad.
Now I have to decide if I want to keep all the internal parts for spares to the p55gt30 or sell them.
What would the recommendation of the forum members be?

[iddomilan]

Re: Panasonic tc-p55gt30

Hey All, my first post.
I recently aquired a TC-P55GT40 with the 7 blink problem. After a bunch of online research, I learned a bunch of parts fail on the SC board causing 7 blinks so I purchased the repair kit from shopjimmy to fix it. After replacing all of the parts with the new kitted parts, I no longer get 7 blinks :-) but the bad news is I get 6 blinks instead :-( If I removed the SC20 ribbon cable, I get 8 blinks, which accoding to my research means a problem still exist on the SC board. I have looked for shorts, but I am not finding anything. Any sugguestions besides buy a new SC board? I am not finding a ton of infomation on the 6 blink problem as I did on the 7 blink problem. I have been trying to reverse engineer the energy recovery circuit which I am hoping will help me find the issue but so far no luck. I spent some time looking for IC16581 but can't even find it on the SC board. I'm stuck, please help........

[gdawg]

Re: Panasonic tc-p55gt30

I would start a new thread. You came in at the tail end of malachi's repair and you will get a lot more help with a new thread.

[iddomilan]

Re: Panasonic tc-p55gt30

I would start a new thread. You came in at the tail end of malachi's repair and you will get a lot more help with a new thread.

Good call, here's a link to the new thread: TC-P55GT30 6 blinks