50" Sanyo Plasma picture going white

[gillisfire]

I have searched through the forum and don't really know what I am looking for. So if I am re-asking a question, I want to appologize. I have a 50 inch Sanyo Plasma Tv that is about 4 yrs olds. I don't have the model number rite now since I am at work. But my problem is, the tv turns on fine and will have a good picture for a little while but then it starts to get real white looking. You can still see whats playing, it just looks real white washed and can get had to make images out. If I turn the tv off for about five minutes and turn it back on, it will work fine for a while and start acting up again. I kinda got used to it while watching tv show, I would turn the tv off during commercials and back on when I thought the show was starting up.

The issue is there nomater what setting the tv is on, such as cable, hdmi, rca, etc. And the sound has no issues at all. It is just the picture getting whited out.

I know my I may may be describing something else when I say it turns white, but that is how I got used to saying it since my kids are the ones that pointed it out. Is this something that can be fixed or is it time to start shoping for a new tv. I am some what used to working with control boards since I work on air conditioners for a living and work on motorcycles on the side. Any suggestions would be greatly appriciated.

[tom66]

Re: 50" Sanyo Plasma picture going white

Some helpful extra info could be useful
- Model # of set; written on rear
- When it goes white are the menus/volume control etc also affected by this?
- Does it continue working when whited out or eventually shut down completely?

[gillisfire]

Re: 50" Sanyo Plasma picture going white

I just got home, so I can give more info now. It is model # DP50749 . When it goes white, only the picture is affected. I can adjust the volume, change the channels, and get to the menu screens. It has never turned it self off, it will still work as normal, just the picture seems to get white (or maybe I should say white darker) and hard to see.

[tom66]

Re: 50" Sanyo Plasma picture going white

Since you said only the picture is affected it is almost certainly a main board fault.
Does it happen on all inputs - for example HDMI, component, CVBS, etc?

[gillisfire]

Re: 50" Sanyo Plasma picture going white

Yes it will happen on all forms of inputs (hdmi, cable, components). It is kinda like when the tv warms up then it starts acting up. I forgot to mention that it first started this summer and I bought a small fan to help move air behind the tv and it worked ok for a couple months. Now it seems like does it just about every 10 minutes. And if we turn the tv off and back on, it will work fine for a little while.

I have the tv off the wall mount and have taken the back off to blow out any dust and to try and see any bad connections. But unfortunately I really don't know what I am looking at.

[gillisfire]

Re: 50" Sanyo Plasma picture going white

Well I cleaned up all the dust and checked all the connections on the different boards. I even ohnmed out all the fuses I could find to make sure they are good. I got the TV put back together and reinstalled all the components and hung it back onto the wall. And I have to say, when I turned it on, the colors were clear and bright. But of course about 15 minutes later it started acting up again. I am not sure if it is getting real white/dark or just darker than it should be. It's just to difficult to see the picture. And as I said above, everything else works fine and the unit does not turn itself off.

So if this is a bad main board, which board am I looking for to be bad? Is it the main mother board J4FE that every site I looked at says out of stock. Or should I be looking into one of the other boards, and how do I test them? Or should I take it to a shop for them to diagnose it for $65 and then parts and labor. (which may be as expensive as buying a new TV.

I know I am asking a lot, so please bear with me. I am a single father with full custody of my 5 kids, so money is tight. And the fact I have my 6 yr old daughters birthday coming up followed by Christmas, I just can't afford a new TV rite now.

[tom66]

Re: 50" Sanyo Plasma picture going white

I'm presuming you own a digital multimeter?

Service manual is here
http://www.tgohome.com/ServiceManual...&Search=Submit

A good, clear photo of your main board would help a lot, perhaps there's a part on the main board going wrong.

[gillisfire]

Re: 50" Sanyo Plasma picture going white

I have a meter, so this weekend when I have more time I will pull my tv off the wall again and see if I can figure things out. Thank you for the link to the service manual. I am going to give it my best to make heads or tells of things. Luckily I took some pictures with my cell phone why I had the tv taken apart. Hope they come through ok.

And I am VERY Thankful for the help you are offering me. You my friend must have some good Karma headed your way.

[tom66]

Re: 50" Sanyo Plasma picture going white

I would suggest trying to heat up parts of this board
https://www.badcaps.net/forum/attach...3&d=1385086482
(the main board)

to see if you can get the fault to occur. Keep heat low. A hairdryer works well.

[gillisfire]

Re: 50" Sanyo Plasma picture going white

I am going to try and do some trouble shooting this weekend. But if my problem turns out to be the main mother board J4FE, is this something I can try and fix or do I need to try and find a new one? I have searched around and can not seem to find one. So any suggestions on what I should try and do?

[tom66]

Re: 50" Sanyo Plasma picture going white

There are schematics for that part, so there are some things that we can check for faults. But most likely you would need to replace the board. It may end up being expensive. You could keep an eye out for TVs like yours with broken display panels, and swap parts around.

[gillisfire]

Re: 50" Sanyo Plasma picture going white

Just thought I would give you a quick update Tom66. You have been pretty helpful, so I thought you would get a kick out of this. I have a window a/c unit close to were my tv is, so I decided to try my redneck engineering abilities out. I took a empty Dr. Pepper box to make a plenum, a clothes drier exhaust duct to run from the a/c to the tv and placed the duct to blow cold air at the main board. Oh, and yes I used a whole lot of duct tape! (it's ok to laugh now) I set this up yesterday after I got off work and so far, the tv seems to be working ok. I guess I am stuck with this set up until I can find and afford a main board. But at least my kids can watch some tv while they are out for Thanks Giving break.

[tom66]

Re: 50" Sanyo Plasma picture going white

Pics or it didn't happen!

[gillisfire]

Re: 50" Sanyo Plasma picture going white

You can laugh, but it is working!

[gillisfire]

Re: 50" Sanyo Plasma picture going white

Well I was hoping I would be posting good news by now. I finally got lucky and found a main mother board J4FE (which are near impossible to find) and changed out the one that was in my TV. I got everything back together and thought it was good to go. Nope.

The picture still goes dark after a few minutes of operation. It turns on and runs fine for about 10 minutes and then you can see the white colors start fluctuating and then the picture goes dark. I put the a/c duct back to blow behind the tv and it works correctly. So as long as the unit has cool air blowing on it, everything works. I will try and get a picture of the screen going dark to help see if anyone has any ideas. But I am getting close to saying the heck with it and buying a new tv.

[tom66]

Re: 50" Sanyo Plasma picture going white

Is it possible you received a bad part?

[freakaftr8]

Re: 50" Sanyo Plasma picture going white

Are you monitoring power supply voltages when this is happening?

[gillisfire]

Re: 50" Sanyo Plasma picture going white

I don't believe it was a bad part. The site I got it from said it was fully refurbished and gave me a 90 day warranty. And given the fact it is still doing the same thing I am thinking that that the problem was not this board.

I haven't been monitoring the power supply. I had put the unit back together and using it since it has been the holidays and my kids have been home. That and this is all new to me. I can build you a house and work on air conditioning units all day, but electronics is something I am not knowledgeable in. I just hate throwing things away if it can be fixed.

It was suggested the problem may be with the X-main board. So I am going to research that part when I get home tonight.

[gillisfire]

Re: 50" Sanyo Plasma picture going white

Well I wasn't to sure how to check the X-main board so I looked for one online. I finally found one and the price wasn't to high so I went ahead and ordered it. So I will post a follow up when I get the new board in. Hopefully this will fix my issue. Or I may end up with a filling cabinet full of extra parts!

I am still open to any other suggestions. All help is greatly appreciated.