A guide to fixing/troubleshooting some common plasma TV problems

[jimmyking]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Looks just like flux to me -- not a fault.

What you need to do is find out where the fault is as it is heat related (as set warms up the fault occurs.)

So use a hairdryer or other heat-producing device and heat up parts one by one, and see if you can make the problem occur much quicker.

I'll do some re-soldering. I'll let you know later.

[jimmyking]

Re: A guide to fixing/troubleshooting some common plasma TV problems

I'll do some re-soldering. I'll let you know later.

I re-soldering lots of (but not all of ) solder points. Still do the same.
I found out something you guys may help me out to understand.

Hot air works! Cold air don't. Hot air blow can make tv works more than 15 minutes. I put a small ceramic heater behind TV instead of heat gun I used. TV last more than 30 minutes before it shut off. Then I tried to push ceramic heater little closer immediately some noise sound came out of back plus some smoke. Now I think power board are toasted. Ceramic heater might have some interference with TV electronically since is not even hot yet when I pushed it closer (about 10 inch from the TV).

Now I'd like to know where I can find another power board or someone still think it is fixable.

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Possibly it got too hot? I wouldn't use more than 50~60C.

[jimmyking]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Possibly it got too hot? I wouldn't use more than 50~60C.

Smoke did not kill the power board. This morning I put hair dryer on low heat and aimed at up right corner of the board. It has been running ever since.
Does someone can provide the explanation or fix for this?

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Can you try focusing your heat on those two cyan/turquoise objects (capacitors) gunked together, near the yellow transformers?
You have temporarily given the TV some life. Enjoy it for maybe a day. It will likely fail in short order.

[jimmyking]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Can you try focusing your heat on those two cyan/turquoise objects (capacitors) gunked together, near the yellow transformers?
You have temporarily given the TV some life. Enjoy it for maybe a day. It will likely fail in short order.

Warm air has to focus on up right corner (as shown in the picture). The same place that producing the smoke.

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

With TV off (& unplugged) shortly after running it can you feel the tops of those capacitors? Are any much warmer than others?

[jimmyking]

Re: A guide to fixing/troubleshooting some common plasma TV problems

With TV off (& unplugged) shortly after running it can you feel the tops of those capacitors? Are any much warmer than others?

All three are warm (not hot) and about the same temperature.

[voy2k]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Hi Tom-

I'm afraid my bold experiment in fixing my Panasonic plasma may be over, but I want to run this by you to see if there are any other options.

I have a Panasonic TH50PX75U that started giving the 7 blinking lights error a few weeks ago. I did some research and was able to diagnose the problem to the upper scan board (TNPA4188). When I unplugged this board, the bottom half of the screen displayed correctly. When the board is plugged back it, it goes back to the 7 blinks error.

SC boards for this set seem pretty easy to find, the SU/SD boards seem pretty scarce. I was able to find a set on eBay from a guy in Canada and ordered them (sold as a pair).

The boards arrived yesterday and I plugged in the new upper scan board. The full display came up perfectly for about 30 seconds, then turned off and the set went back to the 7 blinks error. Pulling the upper scan board brings the set back to displaying the bottom half of the screen correctly.

I know it's impossible to say without more analysis, but I'd love your feedback:

- Did I fry the upper scan board?

- Although pulling the upper scan board stops the error, is it possible that the problem is the SC board?

Appreciate any thoughts you may have.

Thanks,
Voy

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Did you notice any missing lines or duplicated lines on the picture with the new upper scan installed?

[voy2k]

Re: A guide to fixing/troubleshooting some common plasma TV problems

No, everything looked good for the brief time that the display came up.

[voy2k]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Hi Tom-

Any thoughts on what else to try? I'm afraid it's time to bring this set to the tech recycling drop-off, but want to check if there's any other possibilities.

Thanks,
Voy

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

I've got a good feeling your replacement SU was defective, if it was removed from a cracked panel TV, like most of them are. But, I can't be sure. I do think it's definitely fixable. Did you make sure all connections were securely seated, too?

[voy2k]

Re: A guide to fixing/troubleshooting some common plasma TV problems

I was pretty careful about seating each of the ribbons, but I certainly will double-check that. In my research, I did see that these can be a bit finicky, so that's worth another look.

I think you may be right about the SU board, but I'm not sure if I'll be able to find another one. I'll start looking again and see if I can locate another one.

Thanks much for the help,
Voy

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Go by part number e.g. TNPAxxxx not TV model if that helps.

[voy2k]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Definitely. There's a group in Texas that seems to have it in stock so I'll check all connections on the current board tonight and if I don't have any luck, I'll order another board and give it one more try.

It feels so close, I just can't give up yet!

Thanks,
Voy

[MadTogger]

Re: A guide to fixing/troubleshooting some common plasma TV problems

I have a Panasonic TX-P65ST50, had it for just 5 months now and in the last couple of weeks I have been experiencing this issue:



When there is any panning shots, peoples faces tend to smear across the screen lacking detail and very contoured and there is a coloured rainbow effect on these contours.

This also happens when watching Black & White shows.

It happens on all sources i.e. my Sky+HD box and my BluRay player and whether I am watching SD or HD content.

Can this issue be repaired?

Kind regards..,

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Yes, it is more than likely a bad A board, since the TV is new, the A board should be cheap.
You can try and diagnose the fault using the service mode:

• Make sure you're on a working source
• Hold minus button / channel down button on TV
• Press zero three times
• Wait around 10 seconds -- screen will flicker and picture settings will appear to change (they will revert to your settings once you exit the menu.)
• When the menu appears press red twice. Test patterns appear and audio mutes.
• Press red until you get to a gradient test pattern.
• Does the test pattern also show distortion?
• When done press exit or return on remote control, or turn TV off then on again.

[MadTogger]

Re: A guide to fixing/troubleshooting some common plasma TV problems

Thanks for replying.

Tried what you said and couldn't see any distortion.

Regards..,

[tom66]

Re: A guide to fixing/troubleshooting some common plasma TV problems

You got test patterns, but they were clear, even the gradient ones? (Press red once each time to step through the available patterns.)