NEC Px42VM3A lost all display

[Dblueman]

Hey folks,
I was given this NEC PX42VM3A Plasma t.v. Powers up fine. It's the display that I am trying to trouble shoot. At first I had a video display for about 10 minutes or so. And after reading some of the other post, I can say I did see the sparkleys when I first turned in on and then they went away. I was told I would need a new T- con Board but, I am not sure which part # board that is. Those of you familliar with this set will agree with me when I say this set has at least a 100 screws to take out to get to things. Anyone that can tell me which one I need and how much it would be that would be great.
I can include these images if anyone needs pictures. I know most of these pictures are not the T-con board but I wanted to show what the inner workings looked like for this set, Should any one else need questions answered. Thanks everyone!

[tom66]

Re: NEC Px42VM3A lost all display

I've worked on the NEC PX-50XR5G, and it's one of the best plasma displays I've worked on. A common issue with this chassis is the audio amplifier failing, this causes an error signal which shuts off the TV.

[Dblueman]

Re: NEC Px42VM3A lost all display

Hey folks,
What I am experiencing is what has been termed as "Sparkleys" I think?
What I experience is the T,v. powers up fine. But what I see is a flash of colors and then no screen image. Once I had a picture for 30 minutes and then powered down the set, turned it back on and lost the display again. I was told to switch out the T-con Board once but that Did not solve the problem. Tom66 gave me some great advice on how to check the audio amp board which I did and I have aliminated that as an issue.
Anybody have any advice they might be able to give?
Thanks everyone! Many Thanks to Tom66

[tom66]

Re: NEC Px42VM3A lost all display

In a dark room, any glow from the display panel?

[Dblueman]

Re: NEC Px42VM3A lost all display

Not sure what you mean by dark glow.
What it does when you first power up the unit is various colors pixel accross the screen.
Sometimes the full image comes on and fades away. Beyond that, no picture at all.
Just a grey screen,

[tom66]

Re: NEC Px42VM3A lost all display

You need to see if in a dark room you get a dim glow across the plasma panel.
All older plasma panels emit light with no picture, this tells us the priming process is functioning.

[Dblueman]

Re: NEC Px42VM3A lost all display

All I see is the pixels of colors and no glow after that. It's like a flash of colors and then just a grey screen.

[tom66]

Re: NEC Px42VM3A lost all display

The grey screen is what I'm asking about.

In a dark room you should be able to tell if the TV is on or off, without looking at power LED. Can you?

[Dblueman]

Re: NEC Px42VM3A lost all display

Okay I think I understand. I put my finger over the LED light and I would get the color pixels but then nothing after that. No screen of any kind. so in other words you wouldn't see anything. You wouldn't notice if it were on or off.

[Dblueman]

Re: NEC Px42VM3A lost all display

it would be at least back lit correct?

[tom66]

Re: NEC Px42VM3A lost all display

OK, can I have a video of these pixels?

[Dblueman]

Re: NEC Px42VM3A lost all display

Sure how do I send them to you?

[tom66]

Re: NEC Px42VM3A lost all display

Upload it to youtube or a similar site.

[Dblueman]

Re: NEC Px42VM3A lost all display

working on it

[Dblueman]

Re: NEC Px42VM3A lost all display

at one point The whole screen was Bright Green. The video is taking about 10 minutes to up load. I labeled it as nec 42 plasma

[Dblueman]

Re: NEC Px42VM3A lost all display

here's the link to the video. http://youtu.be/tvDJ7FQyMIQ
of the three the last one I believe gives you the best idea and or picture.

[Dblueman]

Re: NEC Px42VM3A lost all display

http://youtu.be/tvDJ7FQyMlQ
try this one instead

[tom66]

Re: NEC Px42VM3A lost all display

Wow, that is very odd. I have never seen that happen before. Is that a good sign?

I'd check if the Vs (or Vsus) voltage is good. I think on this generation of NEC Plasma it'll measure around 165~175V, though the exact voltage will be indicated on the plasma panel.

[Dblueman]

Re: NEC Px42VM3A lost all display

hang on. on the back panel 120v-50/60Hz 3.9A

[tom66]

Re: NEC Px42VM3A lost all display

That's the mains supply. We're looking for the voltage rating on the back of the actual plasma panel, the metal panel where the electrodes on each side disappear into.