Panasonic TC-P55ST30 nothing on screen.

[Malachi]

I picked this tv up today. Had 7 blinks. I checked the ysus tnpa5351, no short on SC2. So I checked the SU board tnpa5340, no short. Next I checked the SD Bauer tnpa5341 and found a short.
I replaced it with a good buffer that I have.
Green led is on on both the SC and SS board

I don't get any blinks but nothing comes on the screen. The bottom of the screen is black, the top half slightly lighter. When I turn it off the top flashes slightly brighter.
It is doing the same thing as the TH-P55VT30 that I never figured out, the thread for that tv is in the forum.

Any ideas?

[tw2005]

Re: Panasonic TC-P55ST30 nothing on screen.

The good buffer, have you had it fitted to a TV and produced a picture before? Do yo have a known good working pair and try replacing both?

All connected ok and the small ribbon betwen the sd/su is connected?

You certainly seem to get some unusual faults .

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

Yes. When I was trying to get the p55vt30 to work, I put every board except for the lower ones that go accross the bottom in my working p55gt30 and the tv worked.
Put them back in the 55vt30, black lower screen grey upper.

So I know this buffer works.

Here is that thread https://www.badcaps.net/forum/showthread.php?t=52873

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

You mean you checked the Ysus TNPA 5335 right? 5315 is not a ysus board.

Black screen when turned on can be a mainboard problem. I got a mainboard thats doing the same.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

In the 55st30 it's not a tnpa5335. It's tnpa5351.
The mainboard worked in the other tv.

[tw2005]

Re: Panasonic TC-P55ST30 nothing on screen.

Yes. When I was trying to get the p55vt30 to work, I put every board except for the lower ones that go accross the bottom in my working p55gt30 and the tv worked.
Put them back in the 55vt30, black lower screen grey upper.

So I know this buffer works.

Here is that thread https://www.badcaps.net/forum/showthread.php?t=52873

Yeah, I remember it. I guess A board was also part of the swap out?

If every board (including C boards) gets swapped out with ones from a working TV and the result is still the same then that leaves just the cabling stuck to the back of the panel or the panel.

I've never seen this before but tat's the only logic I can apply to something like this.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

What does cabling stuck to the back panel mean?
Btw I never did swap the C boards. Just didn't thing that was it.
Honestly, I can almost sell the SC, SS, SU, SD and A board for fir than I can for the tv if is working.
You wouldn't believe the low ballets around here.
I have a working lg 60pv250 listed for $300 and not a sniff of interest.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

Not sure you can see the difference between top and bottom on here.

[tw2005]

Re: Panasonic TC-P55ST30 nothing on screen.

What does cabling stuck to the back panel mean?
Btw I never did swap the C boards. Just didn't thing that was it.
Honestly, I can almost sell the SC, SS, SU, SD and A board for fir than I can for the tv if is working.
You wouldn't believe the low ballets around here.
I have a working lg 60pv250 listed for $300 and not a sniff of interest.

Well on my TVs the white ribbons are stuck to the back of the panel.

I think since this is the second time I'd be tempted to swap every board across from the working TV. Or like you say bail and strip it but it's a fault that has me really curious about what it is.

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

It's a strange fault indeed. I only saw it once on a bad sc board but as the boards work in your other tv it rules it out. You don't hear anything like a buzz from the panel? Maybe it has been damaged someway from the inside?

Few weeks ago i used a to long lock washer screw that went into the panel which destroyed the tv. Now i got a half dark half working screen , using it for testing now. ( Was in a hurry...dumb mistake ).

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

The lock washer screws I used are almost 6mm long. The originals that came out of it are the same.
I give up. Going to save the SD and SU boards as they are they are the same as what my own personal 2 tc-p55st30 take and I'll sell the rest of the parts.

There are no tnpa5351 no suffix on eBay at all. I figure I can recoup my $40 from the tv purchase.

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

Why not replace the C boards and see if thats the problem? Its not that much work and it might give you another tv that you can sell.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

It is a lot to remove the bottom
To get at the C boards and if they aren't seated well it takes forever to adjust.
Plus around here I can't get more for the tv than for the parts.

I also don't think it's the c boards. I have a feeling it's the panel.

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

Ok thats a shame. Panasonic's are not that wanted over there? I can sell a 50GT30 for around $450 over here.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

Not here. People want light weight led tvs. I had a 60" lg 60pv250 for sale for $300, some guy emailed me and asked how old it was. I told him it was made in 2011, he sad that's an old tv.
So I'm sure he will go out to Walmart and buy a crap led tv that if you look at to hard it cracks. Or an led will burn out.
When I tell them plasma are better, better for sports and fast action, they say they don't care.

I also hate the idiots that ask, is it a smart tv? Does it have hdmi?
I say, I put the model number in the ad. Google the damn thing.
Just by those questions I can tell who is never buying. Lol

I tell them you want a smart tv? You are better off buying a chromecast or roku.
Sorry for my rant.

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

No don't be sorry , you are right. Same here!

I recently fixed a 50GT30 and had it for sale for $425. People will email me with dumb questions/suggestions like: "I'll pick it up tonight for $100"
I mean , seriously? What do you think .....

Indeed , led tv's are to cheap. I will always have a plasma for as long as its possible...

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

My own personal tvs are 2 tc-p55st30
I'd like to find 60" or 65"

[Moreno83]

Re: Panasonic TC-P55ST30 nothing on screen.

I got a TX-P50VT50 which i repaired last year. Still working great.

My goal is to get a VT/ZT60 but they are to expensive.

[Malachi]

Re: Panasonic TC-P55ST30 nothing on screen.

I wish I could have repaired the 55vt30. I'm still looking. Last weekend I drove 3 hours round trip to pick up my second p55gt30 with the 7 blink. Put in a good upper buffer and it's like new.

[aaronwt6]

Re: Panasonic TC-P55ST30 nothing on screen.

My own personal tvs are 2 tc-p55st30
I'd like to find 60" or 65"

I want one of those as well. I have the P55ST30 right now and I've love a 60". I'd take any 60" ST, VT, or ZT from the 2011-1014 era. No luck on finding one so far. I believe the 65" might be a bit large for our seating arrangement.