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Discussion Starter #1
Hi all,

I have been reading through the posts and have found my Plasma TV having similar problems, though the TV seems to work sometimes.

Sometimes it goes into the 3 times blue led blinking mode. I unplug, wait for a 2 or 3 minutes and then plug back in and the TV starts working again for the whole night without issues.

As far as I have read, seems that the common problem of all other customers is that it doesnt works anymore after the 3 time blinking issue. For me, it still works and for hours.

Can anyone please advise of where to start and what to do. I think probably there is a small problem and want to avoid of coming a huge one!!

Thanks in advance and greetings!

Bryan
 

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Could be a thermal problem, could be a cap going bad, or lots of other possibilities. Have you downloaded the manual for your set and done any testing or diagnosis?
 

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Hi Lcaillo,

Thanks for the feedback. Currently I am looking into all the posts possible to start troubleshooting. Fortunetely and unfortunately there is so many info out there that I cant get organized or find the best testing method.

Do you have any links or docos which I can use as reference which you best recommend. This weekend I am going to pull the guts out of the Plasma and find a solution.

Thanks for the help.

Bryan
 

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There are suggested sources for service manuals in the stickies in the Service and Support area and in the vendors listings. Some are free, most are a fee between $5-$20.

The place to start with most problems is power supply. Thermal cycling will isolate some things, power supply testing with a scope is best. Sometimes you can see visible problems, sometimes not. ESR testing caps is a common troubleshooting step.
 

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Did you ever get it repaired? I would check the two 3300uf 100v 105 caps in the power supply they are known to get puffy and go bad. Maybe that is the only issue. Maybe you cought it early enough so it doesn't burn out an sdr board.
 

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Discussion Starter #6
Hi,

Sorry for not updating. Totally forget. Well, I will tell you, I changed the caps and it worked perfectly for some time. After 3 weeks the problem started again and very random but much less times.

I havent checked the caps again but I assuem the problem is either the following:

- If the caps are swollen, then it is the whole PSU
- If the caps are ok, then it is the Upper Logic Board since just before the TV goes into protection mode the half top partof the TV starts to fuzz up. So maybe it is the buffers.

Any advise?

Cheers.
 

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Hi,

Sorry for not updating. Totally forget. Well, I will tell you, I changed the caps and it worked perfectly for some time. After 3 weeks the problem started again and very random but much less times.

I havent checked the caps again but I assuem the problem is either the following:

- If the caps are swollen, then it is the whole PSU
- If the caps are ok, then it is the Upper Logic Board since just before the TV goes into protection mode the half top partof the TV starts to fuzz up. So maybe it is the buffers.

Any advise?

Cheers.
Yeah it could be one of the buffers on the sdr board. Maybe a heat issue with the buffers. These boards are not cheap to replace but still less then buying a new tv. I am guessing since you replaced them. The caps should be fine. if your handy enough to replace buffer chips you can buy them on ebay.

http://cgi.ebay.com/Hitachi-Buffer-...028?pt=LH_DefaultDomain_0&hash=item2eb678ce2c
This is for 5 of the buffer chips

http://cgi.ebay.com/3294F-FE3294F-B...651?pt=LH_DefaultDomain_0&hash=item25654526ab this is for one buffer chip.

If your not handy you should just replace the sdr board and ether sell your old one for parts or repair on ebay.
 

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I do not recommend trying to replace the chips unless one has the right tools and experience. At lest practice on an old board. Removing and replacing these chips requires careful temp control and precise alignment.
 

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Discussion Starter #9
Hi all,

Thanks for the reply guys. This weekend I will unscrew the 13,453 screws it has on the back in order to check how are the caps. I am assuming that the caps are in excellent condition. If so, this is very tricky because the uppper logic board buffers dont look at all damaged. They are in mint condition.

Funny thing is that yesterday watching tele, at random times and only twice did the uppper part of the screen (half top) showed white dots for a second or less, though the TV didnt go into protection mode. This is not the first time it happens and used to happen much more before replacing the caps and always shut down. Now it doesnt that often.

Anyways, I think the best solution is to replace the upper board, it is a shame sine i think it will be a cap or one of the buffers.

Me replacing the buffers would sound great but dont have the tools or skills and dont want to take the risk.

Can anyone tell me how much are these bloody boards cost today?

Thanks guys and will keep updating.

Bryan
 

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Hi all,

Thanks for the reply guys. This weekend I will unscrew the 13,453 screws it has on the back in order to check how are the caps. I am assuming that the caps are in excellent condition. If so, this is very tricky because the uppper logic board buffers dont look at all damaged. They are in mint condition.

Funny thing is that yesterday watching tele, at random times and only twice did the uppper part of the screen (half top) showed white dots for a second or less, though the TV didnt go into protection mode. This is not the first time it happens and used to happen much more before replacing the caps and always shut down. Now it doesnt that often.

Anyways, I think the best solution is to replace the upper board, it is a shame sine i think it will be a cap or one of the buffers.

Me replacing the buffers would sound great but dont have the tools or skills and dont want to take the risk.

Can anyone tell me how much are these bloody boards cost today?

Thanks guys and will keep updating.

Bryan
I mostly see them from $104 up to $169 on average. What kind of caps did you replace them with? Maybe the specs are off a little.
 

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Replacing surface mount chips is very tricky. For even a skilled tech, it can be difficult. That does not mean impossible. It depends greatly on your soldering skills and patience. I recommend trying it on an old board first. The big problem is usually getting the old chip off without damaging the board. Putting it back on requires great attention to detail. Patience and the right tools are essential. I have not done a major sticky in a while. Maybe this would be a good one. These jobs are a challenge, but it feels great to do one successfully.
 

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Replacing surface mount chips is very tricky. For even a skilled tech, it can be difficult. That does not mean impossible. It depends greatly on your soldering skills and patience. I recommend trying it on an old board first. The big problem is usually getting the old chip off without damaging the board. Putting it back on requires great attention to detail. Patience and the right tools are essential. I have not done a major sticky in a while. Maybe this would be a good one. These jobs are a challenge, but it feels great to do one successfully.
I never done one ether, but I'm wondering if one of those reflow machines would work to get the chip off the board. Maybe it could be used to put it back on again If someone left trace amounts of solder on the board before reflowing again. I have thought of this but I gave my old board away to the guy who repaired my 2nd board for the 2nd tv. Plus i don't have a reflow machine. I have seen a few web pages now charging a core charge for the old boards. I guess more places are starting to repair them.
 
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