Master thread for Panasonic plasma not turning on - Page 56

This technical guide might help.

Thanks Tomwil. I found this the other day on panasonic's site and from what I can tell, it looks to be my power board. I hear the relay clicking noise when I push the power button or use the remote, but nothing happens after that. I started probing the connections and I'm only getting 2.5 volts to the A board where I should be getting 3.3. There is a small light on the Power board that does not light up, nor does the small light on the SC board either, yet I have checked all the fuses and all ohm out fine. At this point I am assuming my P board is dead, although I don't see any visible signs of a blown voltage regulator or any bad caps. In fact, everything looks great which is perplexing.

Also, the 15 volts to the A board I should be getting on another connection never happens either.

I just found this thread. Yesterday my 5 year old son cracked the screen in three places on my 4 day old panasonic TC-P50ST50. Is it possible to swap a panel from another model like a TC-P50U50 and retain my higher end features or do i just have a huge paper weight??

im thinking about boxing it up for a few years and then look for a non-cracked ST50 that doesnt power on and swap all my components into..

2 things-1 - try to get just the screen fixed-it's possible for less than a couple hundred.
2- this is usually covered under homeowners insurance so it's possible to get it fixed or replaced for the price of your deductible.

I called panasonic, just the part to replace my glass panel is $824 + shipping. got the TV on sale for $999. Deductible is also really high.

I found a good working used 50ST50 on craigslist for $500 obo, i might make them an offer and keep my new one as spare parts.

The U50 panel will have not have a louvre filter that the ST panel does, so you will have more of a glare issue if you swap panels, so the pic quality will not be the same. But some folks prefer a glossy screen if lighting can be controlled.

I just found a 50U50 that has 8 blinking red lights on craigslist really cheap. If i swap the parts in from my ST50 you think it will actually work / be compatibile ? I know i will be missing the filter, but if i have a picture at all we'll be REALLY happy...

I have exact same TV and see the exact same issue as you. Can you share what the issue turned out to be and how you fixed it. It is 18 months old so not sure if panasonic will help at all but I did but it with the Amex card so have the 1 yr extended warranty because of that. I am about to call both of them now. I would like to know how to fix this in case I have to do on my own. Thanks.

A few days ago, my Panasonic TH-50PZ800U came down with the dreaded 10 blinking lights and wouldn't turn on. I would hear the normal two clicks followed by a 3rd click shortly thereafter. I replaced the capacitors on the MC201 and MC301 chips on the power supply board according to stephensank's adivce. The entire repair took about 4 hours and has so far been successful.

Thanks stephensank for the great advice in this thread! I also want to share my experiences for anyone else who may need to do the same fix.

The only 1 uf capacitors that my local radioshack carried were the electrolytic ones with the wire leads. The most difficult part BY FAR about the repair is soldering the wire leads onto the pads on the chip. It is difficult to get the leads aligned properly and then soldered to the board, because they are quite small and close together. I would HIGHLY recommend anyone attempting this to buy the capacitors that have the circular pad ends, because they will be much easier to attach to the chip. Besides this step, the rest of it is pretty straightforward, as long as you have at least some soldering experience.

I found this great youtube video that walks you through step-by-step how to do the repair: http://www.youtube.com/watch?v=LjpGKaBt8hg

The only step not shown is removing the MC201 and MC301 chips from the circuit board. To do this, it is very helpful to have some copper braid to soak up the solder that needs to be removed around the chip leads.

Just my 2c.

I'm working on a Panasonic Viera TH-50PX80U, which has died. There were no blinking lights, so I opened it up. Both the fuses (on board 'A' in the picture) were blown. I'll also note that I could not find any evidence of other shorting, circuit board damage, odd looking caps, etc...

I replaced the two blown and they blew as soon as I plugged it back in. I disconnected board A from the other boards, replaced them again, and this time they did not blow immediately. I tried connecting A-to-C, A-to-B, and A-to-D one at a time, and they did not blow. However, with A connected to C and B (well, at least one of the two wires to B, as shown), they blew again once. Ran out of fuses at that point.

From what I can gather from reading up on this issue, it's likely a problem with one of the boards and that it would need replacing? I'm assuming it's board A in the picture, although again that's just my guess. Is it worth my time/money at this point to even bother? A replacement is maybe $500, so it wouldn't make much sense to spend $200 and hours of time to hopefully fix a 5 year old TV. But I figured I'd ask and see if anyone had a tip/suggestion as to something I might be missing, whether it's time to trash it, or whether it's worth fixing.

Any help is greatly appreciated.

Noob here. Some electronic experience. I am working with a TH-58PX600u 10 blinker - pre power button. None of the TP's on the PA board are shorted to ground. All fuses good on the P-board. Ran through the trouble shooting guide and it seems to be coming from a faulty P-Board, it has bulging 900uf 220v caps 2 of the 3. Removed them from he board and they all meter ~854uf. I am getting around 34vac from the top of all four 220uf 450v caps on the P-board. Found that by accident. Any ideas?
Edited by wmsproul - 1/25/13 at 4:16pm

First, your board actual designations:

A = P-board
B = SS-board
C = A-board
D = SC-board

Second, service manuals that might help:

Panasonic TH-50PX80U Service Manual
Panasonic 2008 Plasma Service Hints
Panasonic 11th Generation Plasma TV

When fuses blow, it usually means that a short circuit exists somewhere. The short probably exists between the P-board and the SS-board.

The three manuals provide flowcharts you can follow to determine which board is defective. It requires some electronic experience.

Edit: Please see this thread for a possible solution involving a shorted transistor.
Edited by tomwil - 2/12/13 at 12:19pm

Our old 42" Panny Plasma is still going along now.
All we do is remove the back 2 times a year and clean it out very carefully

I have a Panasonic TH-50PZ800U from 2008. When I push the power button, the fans start and I hear a couple clicks but then everything shuts down and I get the LED blinking 3 times. According to the service manual, the problem is in the 3.3V circuit but I have replaced both the A and D boards and yet I still get the 3 blinks. Anyone have any ideas on things to check or is it just time for a new plasma? I do have the full technical manual and service manual if anyone has some ideas on what components to check.

Thanks in advance for the help if anyone has any ideas.
Rick

I would check pin 1 of connector P25 and see if you have 15V when starting up. The P-board or the P25-D25 cable/connectors could be defective.

Well, i paid $50.00, got a new P board in my TCP42x1 and nothing has changed. Still don't have 3.3 volts where I should. Will the thing power up and appear to be running if the main screen is out, or what will happen? I'm at a loss. I hate to throw parts at it, but it looks now like it might be the A board which no one seems to have in stock.

In briefly looking at both the technical manual and service manual, it probably is the A-board, but could also be the SC or SS-board. The key there is that there is no SC-board LED lit.

There is a BIN auction currently on eBay, where a seller has ALL the boards for the TC-P42X1 for just $50.

Thanks for the tip. We did a buy it now on this auction and will see if it was one of the boards or the panel. Thank you very much.

Thanks for all the comments on this thread!

I have a Panasonic TH-42PZ80A purchased in Australia approx 4 years ago. I started having the 7 LED blink problem and after a couple of intermittent starts it would no longer turn on.

I removed the power supply board, took it off the heatsink, removed MC201 and MC301 and replaced the suspect SM caps with Jaycar CAT. NO. RE5963 SMD Capacitor Electrolytic 1.0uF 50V - Pack 10 $4.75.

I would have preferred to go with some small poly caps but the ones I could get easily from local suppliers were physically far too big, and being a Sunday morning (RS Closed) and having the tv disassembled in the dining room with very wet weather impending and kids on school holidays I got impatient and went with the electrolytic.

You could probably get away with not removing the aluminium rear heatsink and the MC201 and MC301 boards but I found it easier to do a neat solder on the legs of the new caps. I guess you could probably do the whole job insitu without even taking the power supply board off - but you would have to be a far better solderer than I am!

To remove MC201 and MC301 boards I used a solder sucker. To remove the SM caps, I initially heated up one end, the laid the tip along the side of the SM cap and floated it off.

I took the black plastic fitting off the bottom of the new electrolytic caps, bent the legs down straight (they line up nicely with the PCB pads). I tinned a small amount of solder on the legs then holding the new cap with my fingers (to feel for excess heat) I positioned one leg in the right spot and quickly touched the solder to mount it, then let it cool and touch tolder the other leg. When soldering The black bar needs to be orientated towards the top of the MC201/MC301 board.

The PCB pads are tiny, and as discussed it is quite challenging.

The TV seems to have been working fine since. I accept the electrolytic caps may not last as long as a poly, but I found them much easier to solder on. I did find another image where someone soldered fine flywires onto the PCB pads and then soldered these onto the legs of a larger high quality poly cap. In hind site this may be a better idea.

Also, I noted some posts talking about a firmware problem being a contributing factor. I just checked my version using the software update function in the on screen menus, and I am already at 3.018 which is apparently the latest version available from my reception in Brisbane, QLD , Australia. So I guess mine died at latest firmware we get here.

I found a good video on youtube which shows the process well. The guy in the video also replaces the IC, but I only did the two caps and it seems to have fixed my problem.
http://www.youtube.com/watch?v=LjpGKaBt8hg

I have a Panasonic 58 PZ800U ... and it is giving me 12 blinks.

I've poked through many posts but have yet to stumble upon the issue I'm getting involving no picture.

I have an older TH-42PA20, Build Date NOV 2003.

Upon pressing the power button it clicks once, twice and then the standard TV buzz kicks in. Front red LED is on solid, no blinks. Sound comes on, can be adjusted and you can cycle through inputs. BUT no picture appears for about 10 minutes. Then it became 20. A month later 30 minutes. Then it ramped up to an hour. This week it just won't give me a picture, even after a full day of "charging up".

This began to occur a few months ago. It has been a rock solid set that's been through 4 or 5 moves - so It's a tough old bird. I hate to give up on it. Could this be an issue of age or can this be fixed with some sort of part swap? Any ideas from the pros?

Thanks!

I have a TC-P65S2 and have a similar but slightly different issue and have found ZERO posts related to it- my issue is mine randomly shuts OFF. Anyone had this happen? I'm not sure where I would take it for repair and would rather get in-home service.... ??

I have PANASONIC TC-P54G20 which I bought in November 2010 at COSTCO through American Express (not sure if COSTCO or american express will take care of warranty or not) and yesterday it was on and suddenly stopped working.

I unplugged every other wire and plugged it back on. It's showing 4 Blink issues and black screen. It does not turn on....

I read it on this forum that this might be power supply issue. Is that true ? I'm handy and can buy power supply (i heard that it's low in supply) and try it by myself if Panasonic charges too much ....

Any help would be appreciated ....

===================
Update : Panasonic rep told me to follow this : Unplug the unit and disconnect all the cables from the back. Then press and hold the power button on the main unit and plug the power cord back into a wall outlet while your holding down the power button then after that is done press the power button and see if it powers on.

when I did that.. now it blinks 10 times and not the 4 times ...
Edited by ftaguru - 2/10/13 at 7:45am

I failed to mention, when it does shut off I have no problems turning it right back on, it's just a real pain in the a** when it happens in the middle of a movie because when the tv turns off then so does my BD player.

Update on my issue. I replaced the Power board as listed above and no change. I won the eBay auction Tomwil posted above and replaced my A board with the one I received.

Powered it on and voila, that was the issue. So, now I have two spare power boards and a few other boards, but it was the A board that was causing the problem it appears.

Thanks Tom for assisting me with this repair.

Always great to hear about someone rescuing tech that was once though dead after a bit of effort and a parts replacement.

I feel that I am in a similar situation (see a few posts above), and hold out hope for a DIY solution. But I lack the technical info on what to replace and how to proceed. I've pulled apart my old TH-42PA20 now and can spot no blown caps, browning on boards, or anything melty and out of place. Seems really clean all around. Given that I can pretty much work the TV in every function (minus the screen working...), I feel like logically this is a power issue in terms of delivering juice to the screen.

Any ideas on how to proceed or what board to begin searching for which might control powering up the screen?

Thanks!

This thread mentions where one cause of the fuses blowing out, is from a shorted transistor.

I just wanted to add, my old Panasonic Plasma (50") did this awhile back. I honestly can't remember how many blinks the light was doing. I left it in this state for about 2 weeks, everyday trying to turn it on again to no avail. Eventually I googled it and found a post by someone stating something about unplugging EVERYTHING. Even the receiver, surge protector, hdmi cords, everything to everything; and there were some responses of success to this method so I tried it. Sure enough, plasma came right back on and been working ever since. I turn it on and off all the time since then and no problems at all.

Though I do think the common denominator on this trick working was that we all had receiver's that everything went through.

Anyhow, some of you might try it (dunno if it's been mentioned in this thread, probably has 20 times but I didn't really have time to read it all). I wish I could remember how many blinks I was getting, but alas. I'm not trying to give anyone a false sense of hope, as I'm sure I probably had a different # of blinks than everyone else. But if it was me, I would try it. It definitely worked for me and I definitely had a tv that would NOT turn on no matter what and a red blinking light, like I said for 2 weeks. And again, worked like a charm, no issues since and it also worked the 1st time I tried the trick/method/whatever.
Edited by shpankey - 2/12/13 at 12:45pm

My panasonic 55" GT30 just stopped working. When I try to turn it on all I get is 7 blinks from the power button. The past few weeks I noticed a buzzing sound coming from the top right (when facing the front of the TV) of the TV that would come and go. The past few days I noticed when I turned on the TV the top of the screen would flicker a bit. I wasn't sure if it was my Time Warner cable box or the TV...I guess it was the TV. My set is a few weeks over a year old but I did get a Square Trade Warranty. So I filled out a claim and I guess I'll have to see how this goes...bummed.

I didn't look through much of this thread as they're are many pages. So I apologize if I'm posting something that's been posted multiple times before.

You may want to contact Panasonic service. There exists a possibility that Panasonic service will cover 2011 plasma problems with the SC-board, which affects most models and where a firmware update has been issued.