How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask TV Tech1 Your Own Question

TV Tech1
TV Tech1, Technician
Category: TV
Satisfied Customers: 5221
Experience:  30 Years experience. Authorized Warranty servicer.
Type Your TV Question Here...
TV Tech1 is online now
A new question is answered every 9 seconds

Panasonic TH-50PZ85U wont power up

Customer Question

I have a Panasonic TH-50PZ85U that will not power on. When the power button is pressed, the red power LED blinks twice, which the internet suggests means there is a problem with the 15v "D" Board. The TV was given to me because of the current condition with no warranty. I am somewhat technically able...are there any easy tests that I can do to figure out which board is faulty to buy and replace? If it is the D Board, is that something I could do myself...? ...if it is a power supply is that something that can be done by layman (is it true that the power supply needs the voltage adjusted after install even if an exact part match is found?)? <br /><br />THANKS! <br /><br />Jared
Submitted: 4 years ago.
Category: TV
Customer: replied 4 years ago.
Relist: No answer yet.
Expert:  TV Tech1 replied 4 years ago.

My experience has been when you get the 2 blink error code it's never the D-Board....

 

Take a look at this Block diagram...it gives you the basics of what makes your TV run.

 

graphic

 

 

 

 

Now, you see on the LEFT side the 15V(p) powers up the D-board, and on the RIGHT side is the power supply where the 15V(p) is created. That 15 Volts is shutting off -- You can verify this by looking at any fans you have on your TV set, near the top vents. Shine a flashlight in there, turn on your TV set, and if they spin, you have a good 15 Volt supply. And that means your D-board is getting what it needs.

 

Now, LOOK at the LIGHT BLUE highlighted section in the Lower right side of the power supply....it turns OFF the whole power supply if there is a fault on the SC or SS board. We'll need to verify that.

 

So....the tests aren't easy, they are somewhat complicated. You will need a good voltmeter and a screwdriver.

 

As for adjustments...it's not as big a deal as they make it out to be, but it's always wise to check the voltages to make sure it's within specifications.

 

But I will tell you this...If SOMEONE gave you that TV and said "it's too expensive to fix it - we bought a new one" then believe them..

 

Some of these can turn out to be expensive.

 

So tell me, you got it at no charge, and with no warranty. Tell me what the original owner told you so I can get a "feel" for the condition of the TV set.

 

 

 

 

Customer: replied 4 years ago.
Original owner is my father-inlaw. The TV was on the wall for one month when it just stopped powering on. He had bought it with an AMEX card, so he called them up for replacment under the card and they sent sears to inspect. According to the case file (vauge) they replaced the power supply PCR, which did not solve the problem. The then needed part was on backorder long enough to where AMEX just issued a replacment, the repair effort was abandoned mid-work, and to my complete disbelief, AMEX did not want the defective TV back...which is how it comes to me. Dad has a new one, and doesn't care to deal with it.

I opened the back up and and it looks like someone was in the middle of testing it...a few cables unplugged. I put them back (pretty clear), tried a couple of simple tests that the internet had to offer up in hopes of discovering the faulty board, and none of the easy culprets did what the tests said they should show...but who knows if I did the right things...

And that is where I am at...oppertunity of a lifetime to make this TV work, even for cost of replacing parts...

Thanks,

Jared
Expert:  TV Tech1 replied 4 years ago.

Well if they replaced the power supply in there then half my work is actually done. That's kind of good, but what that leaves us with is The Zsus and Ysus and X-drive boards (these are generic terms -- the ysus is the SC and the Zsus is the SS, and X-drive boards are the C1 C2....up to C6 Boards.

 

Now, did you check to see if the fans spin then stop? If so, then the D board is likely functioning.

 

But we can check that out....Here is a picture of where the boards are located, and all plugs always start with the letter of the board it is connected to, so you'll find SS34 on the SS board.

 

graphic

 

Let's make sure the power supply is ok-- do you have a voltmeter available for testing?

 

If not, Sears and Lowe's for Cat 3 meters.....

 

http://www.sears.com/shc/s/p_10153_12605_03482141000P?keyword=multimeter&prdNo=2&blockNo=2&blockType=G2

 

http://www.sears.com/shc/s/p_10153_12605_03482334000P?keyword=multimeter&prdNo=4&blockNo=4&blockType=G4

 

http://www.lowes.com/pd_292768-12704-61-310_0_?productId=3095863&Ntt=multimeter&Ntk=i_products&pl=1&currentURL=/pl__0__s?newSearch=true$Ntt=multimeter

 

http://www.lowes.com/pd_136122-12704-61-340_0_?productId=3127727&Ntt=multimeter&Ntk=i_products&pl=1&currentURL=/pl__0__s?newSearch=true$Ntt=multimeter

 

We'll be testing mostly DC voltages so the first ones are adequate, the second ones just have autoranging so you don't have to worry about smoking the insides of the meter if you have it on a low voltage setting and test the 200 Volt Vs voltage....

 

 



Edited by TV Tech1 on 6/13/2010 at 12:08 AM EST
Customer: replied 4 years ago.
I am at work all day today (lowes) I'll take the cheap voltmeter I have to work and see if it is "cat 3".

I didn't notice it before, but the fans do kick on for a second before the auto-shutdown.

I was not expecting this level of help...can the price be adjusted later?...this is worth more than $18 to me.

Thanks...
Expert:  TV Tech1 replied 4 years ago.

If you want to add, all you do is TIP- Bonus me...I get more of the TIP than the posted Labor

 

The ratio is 75 / 50. I think that's why the other guys emphasize "A tip is greatly appreciated" Me, I look at it as I chose to do it for the Labor...

 

And so...a BONUS is greatly appreciated !

 

Also note, a Cat 3 or Cat 4 is really only to let you know the maximum voltage level a meter can handle...You need to handle 250 Volts for the Vs Voltage and everything else is a lot less..

 

As long as it handles 250 Volts DC we're good....

 

Now, where should we get started? Let's make sure all the power voltages are at the power supply. It's redundant if the TV repairman left the new power board in, but we don't know that for sure....

 

I kinda prefer to do pictures because I generally save about a thousand words. So if I'm not answering quickly, I'm working with pictures, and I generally take a good hour to get them ready.

 

Ok, First thing, let's get you familiar with your TV set. Set it in an area where you have good lighting, an AC plug and a table with some room on it.

 

Next, remove the screws out ot the back, and leave it on the stand for testing. Make sure you can plug it in, and hopefully look at the screen and the blinking LED.

 

Now once you remove the BACK -- Here is where your BOARDS are located and the PLUGS are located.

 

graphic

graphic

 

We will be testing the power supply first to make sure our power supplies are working.

 

Ok, now...on the back of your TV set, remove the power cord and then remove the connectors highlighted in green and circled in YELLOW....this disconnects the entire PANEL DRIVE system and leaves the Fans, the A board and D board RUNNING.

 

graphic

 

Check this Jumper--- MOVE it over to P 12 Connector on the power supply board.

 

graphic

 

 

 

Plug it back in, and Turn it on --- Do the Fans stay running? All four of them?

 

Does it shut down? Does it blink a different code?

 

If if stays ON --- then measure these points on the plugs located on the P board.

P Plugs are on P-board, SS plugs on the SS board , and remember that PIN 1 is always the UNIQUE -colored wire on a plug....like if you have ALL BLUE wires, then Pin 1 will be WHITE or a different color

 

 

Check these voltages on the power board

 

graphic

 

 

 

 

 

 

 

 



Edited by TV Tech1 on 6/13/2010 at 6:00 PM EST
Customer: replied 4 years ago.
Well,<br /><br />I got all the pins disconected, plugged it in and turned it on and got the same result...all 5 fans turned on, then a click is heard, and they shut off...led begins the 2 blink code untill power cord is unplugged.<br /><br />With this result, do you still want me to check these voltages...and if so, and forgive me, could you give a quick explanation of where to place the the testing prongs to give to the correct readings without wrecking anything and verify for me that I should be using the AC Volts setting? <br /><br />Thanks
Expert:  TV Tech1 replied 4 years ago.

OK, the important part is did you take that jumper off of SS34 and plug it into P12 on the power board. If not then it needs to be put on pins 8 to 10 because it makes sure the power supply isn't being tripped into shutdown.

 

Now if you DID move that jumper, then we most likely DO HAVE a bad D Board ! But I think we should check some of the other circuits supplied -- The audio amp is one other possibility and obviously the fans work, and the other possibility is the D board.

 

Ok, here is the 15 Volt path....

 

 

graphic

 

 

 

Plug 6 on the power board supplies 15 Volts to the sound circuit. Let's unplug that and see if our 2 Blinks disappears.

 

 



Edited by TV Tech1 on 6/13/2010 at 10:50 PM EST
Customer: replied 4 years ago.
I did move the jumper for the last test. Took it out of SS34, took the plug out of p12, and placed the jumper on the far right, pins 8 -10.
Expert:  TV Tech1 replied 4 years ago.

That's the correct way to do it. Pull P6 off the power board and let's disconnect the Sound amp....

 

 

Customer: replied 4 years ago.
I unplugged Plug 6 from the power board (in addition to all of the previous disconnections) and it changed to a 10 blink. Do I need to reattach everything else and then try to see what P6 does?
Expert:  TV Tech1 replied 4 years ago.

Ok, reconnect Everything back up, the Drive boards aren't the cause and P6 carries every voltage that the A Board uses, so we can't use a voltage measurement to check the Sound circuit.

 

We're down to the P Board, the A-board and the D-board being the cause of the 2-blink code....

 

Now make sure that the SS12 plug and the SC 20 ribbon cable get reconnected first before doing any other cables...that ribbon cable has a couple tabs on the edge that go UP and OVER a couple tabs on the socket, make sure the ribbon's tabs are inside-- then lock it back down. If you don't you can damage that ribbon .

 

Once that's done, get out your voltmeter and start at the top center of this picture.

I suspect you will end up seeing the one board I never see fix the problem actually fix the problem -- make sure you measure the 15 Volts by connecting your red test probe FIRST, THEN turning on the TV set. -- Once those fans stop you can't measure it.

 

Here is a step-by-step troubleshooting guide....

If you need help with it, let me know, ok?

 

graphic

 

 

 

 

Customer: replied 4 years ago.
I'll give it a shot...I can't screw the T.V. up by testing right? ...just the meter?

I'll get back to you, hopefully with the answer, PMT and Tip...thanks for your time and awesome explanations
Expert:  TV Tech1 replied 4 years ago.

You can't screw up the TV or the meter, you'll be basically testing for 15 Volts, and testing for resistances below 50 ohms (shorts) -- I don't expect shorts if the fans are running, but there is a feedback signal from those fans that would show up as 11 blinks. So I think your fans are ok, they aren't pulling down the 15 volt supply.

 

Just follow the path on that picture, and if you are not sure of the results, just point it out and I'll walk you through it.

 

Gonna be signing off tonight. Let me know the results ok?

 

 

Customer: replied 4 years ago.
First...it just occured to me as I am writing, that as I did the tests, I was not sure if when the instruction was to measure at Pin 1 of p7 if that meant the pin on the board, or the pin in the wire harness. I made measurments at the harness without thinking about it...if this is incorrect I imagine I will have to re-do...just let me know ...if that is not wrong, then on to what happened, and what I wrote before I realized I might have done it all wrong ~~~>

Ok...if you don't mind...review my nube work on the multimeter as I am new at it...

I removed connector p7 and measured resistance between pin 1 on connector p7 and ground and got a reading of 36.25 MΩ, which I took to mean no short circuit...so...

I went left to measure the voltage of pin 1 on connector P7...
Connected red to wire harness pin 1, black to chassis, connector was not on board

Some strange things happened...first, when plugged in, the click of the power coming on was constant on and off every second or so. The meter showed about 1.5 VDC, fans did not run.

Then, I thought that I might need to do this with p7 hooked up to the board. I connected p7 to the board, put red on pin 1, black on the chassis. Plugged the set in, and again about 1.5 VDC, but this time without the constant clicking. Finally, I hit the power button while monitoring the meter, and although I didn't see the fans come on, for a brief second, the meter jumped to ~15VDC.

I am in serious doubt of my results...can you make any sense of this?
Expert:  TV Tech1 replied 4 years ago.

Oh you did it JUST FINE...Of course I recommend you check the resistance with the plug actually plugged in, but the results tell me there is NO SHORT as I suspected, and you got 15 Volts too...

 

Now walk thru those diamonds and answer the questions and where do you end up at??

 

 

Customer: replied 4 years ago.
***Resistance with the plug in is 1.75 kΩ...does that still work?***<br /><br />...The MUCH cheaper and more available D BOARD that is never the answer?
Expert:  TV Tech1 replied 4 years ago.

That's GOOD resistance, I like to see that. NO SHORTS on 15 Volt circuit

 

 

Looks like it is this time, but I've dealt with others that weren't tested as thouroughly as yours is either. There's more to it as you can see with our troubleshooting.

 

Your part number is TNPA4439AJS

 

http://www.shopjimmy.com/panasonic-tnpa4439ajs-d-board.htm

 

Good price

 

http://www.partstore.com/Model/Matsushita/Panasonic/TH50PZ80U.aspx?p=1&z=50&c=da4ab2c26d3cad2abbb5f2875575cafe&bs=Category&bd=Asc&ms=Category&md=Asc&k=&on=

 

Horrible price on that one!

 

I'd go with Shop Jimmy --Good parts from them.

 

If you have any questions, just ask

If you are finished, please press the ACCEPT button.

 

Thank you.

 

TV Tech1, Technician
Category: TV
Satisfied Customers: 5221
Experience: 30 Years experience. Authorized Warranty servicer.
TV Tech1 and 5 other TV Specialists are ready to help you
Customer: replied 4 years ago.
I can see how so many things can change the result of simple tests. I am ordering the part and crossing my fingers...here goes nuthin!

Thanks Again

Jared
Expert:  TV Tech1 replied 4 years ago.

I hope you buy it at a place you can return it without any restocking fee, but I don't think that exists out there anymore--Most have a 10% to !5% charge, but I'd rather have that then a no-returns policy

 

While everything points to the D board, I've been bitten 3 times with that 2 blink code, That's why I'm putting MORE effort into troubleshooting yours...The others I just trusted that Panasonic's codes always pointed to the correct board. Now I see they hide the NEXT most likely boards, like the A-Board

 

Let me know what your results are on that, I really want to get a good working history of what works and what doesn't -- Ok

 

And thanks for the bonus, really appreciate it.

 

 

Customer: replied 4 years ago.
well...i put it in this morning and still the 2 blink remains....is there a chance that I zapped static zapped the new board or didn't get one of the ribbon connections exactly right? I was VERY careful...bummer
Expert:  TV Tech1 replied 4 years ago.

I doubt you zapped the board -- for some reason this 2 blink code is VERY popular and it's been the Pain in my -- troubleshooting experience.

 

Time for the BIG GUNS ....

 

I will NEED your model number and your SERIAL number.

 

I'm going to call the TECH LINE Monday and let them know the 2 blink code points to the D board, the 15 Volts fire up the fans, NO SHORTS and I'M Getting the Answer from the Panasonic TECHS.

 

I'm presently working on Three -- Two Blinkers here at JA , and no matter how hard I try to isolate this down, the TV's don't work. Those Techs have got to have the answer.

 

But to get it, I have to tell them that I'm actually working on it I really need your serial number .....

 

Customer: replied 4 years ago.
you got it...

MG80430140

There are some other numbers on the sticker as well:

MC127F19T11
Expert:  TV Tech1 replied 4 years ago.

Great...I have to call them MONDAY, so bear with me

 

OH !! JOY !!

 

I just talked to the Panasonic TECH just tonight!

 

He said I'm getting a misdiagnosis by the computer -- The Vsus voltage is shorted, that voltage comes off the same transformer as the 15 Volt supply and it triggers the 15 volt SOS circuit !

 

I KNEW that there had to be something not listed in the troubleshooting.

 

Alright this is what we need to do....

 

Test the Vsus voltage with both SC and SS boards disconnected from the power supply -- We need to see if the power supply is getting up to 200 Volts or not.

 

-- Then we need to see if we lose the Vsus when it's connected to the SS or the SC board.

 

We test the voltage while the fans are running and stop when the Fans stop running

 

We are getting some MAJOR storm real quick...Unplug the Blue/White two wire cable off the SS and SC boards -- those are on the left /right sides. plug your voltmeter probes into the Blue /White cable to test the power supply by itself....hit the power, and if you get 180 to 200 Volts the power supply is good.

 

The plug in the SS and fire it up....Good Voltage -- Good board

Bad Voltage -- BAD BOARD

 

SC board NEXT.... Plug it in --GOOD voltage GOOD Board BAD Voltage BAD BOARD

 

I'm signing off for an hour Major STORM !!

 

 

 



Edited by TV Tech1 on 6/19/2010 at 12:21 AM EST
Customer: replied 4 years ago.
I am not getting a result of any kind...maybe i am doing it wrong...

I unplugged both the SS11 and SC2 connectors from the board, and have tested both plugs by sticking my prongs into them and then turning the set on...no voltage readings in either...

did I get you instructions correct?
Expert:  TV Tech1 replied 4 years ago.

Ok --- FIRST. Make sure those cables are connected to the Power Supply board in the center. Fire up the TV and check that voltage FAST. It's going to disappear, so I'd plug those probes directly into the Socket to test There should be a picture/block diagram of the power supply above in our postings.

 

Follow the directions I gave you.

 

If you still get No voltage let me know.

 

 

Customer: replied 4 years ago.
I just noticed that your picture is a little different than my set...I have a sub power board to the right of my main board...but I am pretty sure I have the connections you are talking about...

There is a big, blue and white two wire cable that goes from the power board to SC and a similar grey and white two wire cable that goes to SS.

To be sure I was getting a good test, I unplugged the wires from the power board itself and tested the voltage at the pins for the connectors on the power board. With both disconnected, it shows no DC V's to speak of at power on...even briefly...on either connector
Expert:  TV Tech1 replied 4 years ago.

Yeah, sorry, some of my "memories" said BOTH were Blue and White, I guess I should have said the big' ol honkin' Two wire cable at the top of the boards...Main transmission lines is what they are.

 

So NO POWER out of your POWER SUPPLY -- That's the Failure, --- Now I want you to make sure your boards are disconnected from the power supply and measure the resistance "on those honkin two wire cables -- separately. We want to see if the LEFT SC board is shorted or the RIGHT SS board is shorted.

 

We NEED the power supply -- let's see if any of those blew out the power supply. And if that was the NEW power board -- IT DID.

 

Also note, I have found Panasonic uses some Generic Pictures and leaves ouf the variations on their Pictures/Block diagrams - Who wants to muddy up the picture so much you can't find the info easily?

 

Can you RETURN the D-Board to the supplier? Your old one is likely to be good, so you should call the supplier and see if you can.

 

 



Edited by TV Tech1 on 6/19/2010 at 10:20 AM EST
Customer: replied 4 years ago.
testing the honking cables gives me resistances in the MΩ range.

I should be able to return the board to Jimmy and get 60% back. I more bummed that it looks like the power board because of how hard those are to get.
Expert:  TV Tech1 replied 4 years ago.

We can only assume that the previous tech installed the new Power board and it didn't work either.

 

WHY? That's what I'm thinking...

 

If you get readings in that high, it LOOKS like your SC ans SS board are good, but I also remember that Panasonic was sending us out with the POWER the SS and the SC boards on certain models under warranty a couple years back...I'm beginning to suspect you have one of those models, due to the fact the Sears Tech installed JUST the power board, then AMEX exchanged it due to slow turnaround.

 

I'm going to get ALL the PART NUMBERS for you FIRST....

 

Power Supply --- ETX2MM704MGL

 

SC board -- TXNSC1RJTUS

 

SS board -- TXNSS1RJTU

 

I'll find suppliers for all 3 boards next.

 

P BOARD

 

http://www.shopjimmy.com/catalog/product/view/id/169538/s/panasonic-etx2mm704mgl-power-supply/

 

https://www.encompassparts.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=7712083

 

http://www.tristatemodule.com/p-22-etx2mm704mgl-panasonic-tv-module.aspx

 

Geez -- No one has it ! Could take 6 WEEKS to get these.

 

Are you good at soldering??

 

If so, we MIGHT be able to repair the board, as long as the transformer isn't shorted

 

 

SC BOARD

 

http://www.shopjimmy.com/catalogsearch/result/index/?q=Panasonic+TXNSC1RJTUS&limit=5&mode=grid

 

 

http://www.moduslinkptstvboards.com/TXNSC1RJTUS-P24900.aspx

 

 

SS BOARD

 

http://www.encompassparts.com/products/?TXNSS1RJTU

 

 

http://www.shopjimmy.com/catalogsearch/result/index/q/sj-txnss1rjtu

 

These are in stock.

 



Edited by TV Tech1 on 6/19/2010 at 11:05 AM EST
Customer: replied 4 years ago.
I really don't have any experience with soldering unfortunatly. I guess that's the end of the road for me then...as I understand it...with no power readings at P2 and P11, the board isn't supplying the TV with power and is bad, but no one has them (P boards) because they are obviously a poor quality part, and everyone needs one.

Bummer
Expert:  TV Tech1 replied 4 years ago.

They WILL get them in stock.

 

Got any friends skilled in soldering ? -- You really don't have to be SUPER -Good in that section of the circuit --- we need to test the transformer for OPENs and Diodes for shorts and maybe some CAPS for shorts.

 

The only thing we don't want is an open transformer....We might as well check them, if you have the meter, let me know , and I'll post the schematic (for me) and walk you thru the test.

 

Also, look up "how to solder" on google, I'm sure they have You Tube videos too.

 

Don't give up -- always look for an alternative.

 

 

Customer: replied 4 years ago.
hey...I am willing to try anytihng...and if the board is bad...than why not?

Expert:  TV Tech1 replied 4 years ago.

Ok, these are the schematics for our testing points.

 

This is the INPUT side...

graphic

 

 

 

This is the OUTPUT Side....

 

graphic

 

This is a picture of the board with location of the parts to test.

 

graphic

 

Now in this LAST picture I highlighted TWO TESTPOINTS IN GREEN -- Test point 1 and 2 -- put your red and black probe on those two, turn on the TV set and you should get around 170 to 220 Volts DC -- that's our power to the transformer.

 

Also check the FUSE F201 highlighted in YELLOW -- let's make sure that's not open.

 

After those two tests, Remove the board from the set, flip the board upside down, and find those pins highlighted in blue -- the two on bottom is the PRIMARY WINDING and should have LOW to no resistance and the UPPER two blue dots are the SECONDARY WINDING and they should also have a Low to NO resistance on them.

 

We JUST want to make sure they don't read 10,000 ohms or higher, because if they DO -- Then that transformer is bad.

 

Now, I highlighted the diodes for a QUICK TEST -- Using your OHMMETER / Resistance setting go to the Plugs -- P2 OR P 11 -- either point will work.

 

Put your probes on Pin 1 and Pin 2 --- In one direction you should read over 10 million ohms, and in the other it should read 1 million or LESS

 

All those are the NORMAL readings ...

 

Tell me if you find that fuse open or the transformer Primary or Secondary open or ANY DIODES open or shorted.

 

If you need help, I'll walk you thru it.

 

Don't forget to measure the DC voltage across test point 1 and 2 -- we want to make sure we have power there.

 

 

Customer: replied 4 years ago.
1st thing... Tested DC V's across test points 1 and 2...388 V's !? The voltage stays at 388 untill you hear the shutdown click and the fans stop, then it falls steadily by about 1V/second regardless if the probes are on or not...I could watch it fall from 388 or take the probes off and put them back on a minute later and it is still falling at the same rate. Is it normal to have almost 400V at those test points? (good thing I got a type III)

Second...I tested the resistance of the fuse by putting the probes at the top and bottom of the fuse...result = 0.1 Ω, which I take to mean good connectivity, which I assume means fuse OK?

Let me know what you think about the high voltage at test points and i'll continue with the testing tomorrow...

Thanks!
Expert:  TV Tech1 replied 4 years ago.

That's NORMAL...some power supplies only create 170 Volts Raw DC to power up the transformer, some use a Voltage DOUBLER setup that doubles the Voltage -- That's what you have.....

 

Now, since we DO NOT have any voltage coming out of the SECONDARY SIDE of that transformer -- check those Sky-Blue Test points for OPEN windings. The 388 Volt side is what we call the PRIMARY and the blue dots on That side is your primary winding, the blue dots closest to the P2 /P11 plugs is what we call the SECONDARY side of the transformer.

 

So check the Blue dots next, then do the resistance test with your Test meter by turning on either the DIODE test or the RESISTANCE test -- Put the Red/Black probes on the P2/P11 pins in one direction, then the Other direction....you should read either Hi resistance one way and LOW resistance the other way (like 200,000 ohms low, and 8,000,000 high )

With the DIODE test it should read OL for open and maybe 1.4 to 3.2 for forward biased diodes

 

Diodes act like VALVES...they allow current flow in one direction and No Flow in the other, so that's why we turn the test probes around on P2/P11

 

IF you find good, somewhat low reading on the Sky-Blue pins, and you find the Diodes get a good High / Extremely Higher reading using the ohmmeter, then we will move to the OSCILLATOR IC that drives the primary side of the transformer and creates the VSUS voltage.....

Customer: replied 4 years ago.
The P2 / P11 resistance test looks good, but the readings do jump around a little...but it is in the K ohms one way and the high M ohms the other, on both.

In regard to the sky blue test points...I took the P board off the set, but it is pretty heavily attached to a metal tray with lots of connections....do I need to remove the board from the tray to do the test...and is it still HOT because of capacitors?
Expert:  TV Tech1 replied 4 years ago.

Hmmm, could use a picture of that TRAY, I don't think I'll see that in the schematics. Is it screwed in or soldered ON ??

 

 

As for the caps, measure across them for voltage and keep the meter on it for some time to drain it down to 50 Volts or less so you don't get hit.

 



Edited by TV Tech1 on 6/20/2010 at 3:25 PM EST
Customer: replied 4 years ago.
Board was screwed on...I got it off...

I think I found the test points for the transformer...they are in about the right spot as far as I can tell from the sky blue dots, and there were black arrows printed on the board pointing at them.

Anyhow...the resistance of the lower 2 is .1 ohms and the resistance of the upper two is 140 K ohms.

The readings for the P2 / P11 test jumped around a little, but I saw the desired result on both... K ohms in one direction, M ohms in the other...
Expert:  TV Tech1 replied 4 years ago.

Hmm that secodary is a little HIGH....and that MAY mean we have an SC or SS board eating that transformer. That of course means that the boards will test ok with LOW voltage from a meter, but it blows when 200 Volts is applied.

 

I have to look into that part a little further....

 

Get back with me. I think we better test the power supply oscillator to see if that's damaged -- I'm heading for bed, and tomorrow I'm working, but I'll try to post the test for the oscillator -- we're just going to check the on/off switch, the Main power to it, and maybe a FET or TWO if accessible. Then we'll power it up and see if we get AC voltage on the PRIMARY -- That's what the oscillator does, it oscillates.

 

And if it oscillates we replace the transformer -- if it doesn't we replace the oscillator.

 

Either way, I think it would be wise to replace the SC board, the SS is less likely to short out.

 

Customer: replied 4 years ago.
your level of knowledge is rediculous...i'll get back with you tomorrow...thanks for eveything you have done so far...
Expert:  TV Tech1 replied 4 years ago.

I LOOKED at 3 different parts....none in stock, and the cost of all 3 ran right around $100....[[ That's rediculous]] I guess that's the "word of the day" Say the word, win a cup of coffee...

 

graphic

 

 

Unfortunately that has put us back to waiting for the power supply.

 

I suggest the SC board, and the Power supply board be replaced as a minimum, and if you want to, get the SS board for good measure, because Panasonic always tells me to order all 3 under warranty. They want it fixed the first time we come out to the customer's home, not 3 trips later.

 

We have pretty much got it isolated, and the parts are listed, and while they aren't presently available, I suggest checking those websites, and using the part number on Google about twice a week to find the power supply board.

You get that, you can finish the job.

 

But don't forget the SC and SS boards....

Once you get the power board, order the SC board at least....and put that board in first before installing the power board.

 

Good luck, and you can always get back with me later on this, just KEEP the last email with the URL in a safe place.

 

And thanks, XXXXX XXXXX a good time working on this project.

 

 

Customer: replied 4 years ago.
sweet....thanks again
Expert:  TV Tech1 replied 4 years ago.

Sorry I couldn't find a FAST way to fix your TV.

 

Be aware -- IF you order from some websites, and the part is backordered, they may cancel the order automatically.

 

To verify this, you should call by phone and ask them if they cancel backordered parts.

Expert:  TV Tech1 replied 4 years ago.

DUDE !!

 

This is important !

 

I just got this from another guy with a bad POWER BOARD !

 

I did find a P-board at Tri-State (by phone, "not in stock" on the web site) & ordered the SC and SS boards from them also.

Make the call to them.

http://www.tristatemodule.com/



Edited by TV Tech1 on 6/24/2010 at 10:17 PM EST
Customer: replied 4 years ago.
I have been trying to get throught to them...but I work all day so it has not been easy...hopefully I can call next week and hopefully they have another one in stock. That is wierd that it would not show on the site....do you think they sold it to you because you are a tech? ...why would they not list online?
Expert:  TV Tech1 replied 4 years ago.

No that's not the case, someone else phoned the company (another customer with your same problem) and found out that they had ONE LEFT...

 

Back to the drawing board...

 

Phone some of the other places, because he was informed the website isn't updated as much as it should be - it's likely others aren't

 

 

Customer: replied 4 years ago.
hey...

I am finding some power supplys listed as pulled from my model, but the part numbers vary a little i.e

"ETX2MM704MG N"

do you think this would work...or are they different somehow?
Expert:  TV Tech1 replied 4 years ago.

ETX2MM704MGL -- compared to ETX2MM704MG N

 

Sounds awfully close...

 

GOOD NEWS -- FULLY INTERCHANGABLE, they come from the same chassis.

 

Go ahead and Buy it.

Customer: replied 4 years ago.
so...the guy had the wrong part number listed...actual part number: ETX2MM704MG H

interchangable?

thx
Expert:  TV Tech1 replied 4 years ago.

I think the LAST LETTER is the Version...

 

 

"A" was the first run, the H is certainly AFTER the "A "version - so hopefully you get the "Z" version with the freshest parts....

 

When you install the board, match the Voltages listed on the tag stuck on the Plasma panel itself...you'll find a small adjustable knob clearly labled as to what knob adjusts what...and the Voltages all have a Test pin, or a connector with it clearly marked...either place will do fine to adjust them. Then plug it into the board on the left and the right (the main cables that power them up) Set them with the cables disconnected first, then unplug the AC cord.

 

You should only have to set Va or Vs.....and either Ve or Vg. That's all the letters that ALL plasma manufacturers use -- so don't go looking for ALL of them, just look to see if there is a Va adjustment and a Ve adjustment on the power supply. That tag also lists MORE Voltages, but these don't have adjustments, just checkpoints as they track those two main voltages.

 

Don't touch any other knobs on any other board, just those on the power supply board. !!

 

 

Customer: replied 4 years ago.
alright...well i'll go ahead and order the board from the guy...if you don't mind I may get back with you on how to make these tests...

thanks
Expert:  TV Tech1 replied 4 years ago.
Sure, I think i can make a picture of that adjustment....
Customer: replied 4 years ago.
welll...success at last...however they failed to send me the SC board I ordered...so in a fit of being fed up, I just put the P board in - and it worked...cause for celebration, or over-excitment / it'll break again?
Expert:  TV Tech1 replied 4 years ago.

Sounds like the SC board is good-- when they blow they blow...and they take out the power supply with them.

 

If you are up and running, then you are good.

 

You see the White tag on the back of the actual display panel? The one with the Va or Vs settings on it?

 

Your new power supply voltages should be matched/adjusted or verified to be within one volt of the Vs /Va and (I think Panasonic calls it ) Ve voltage (or it could be Vg)

 

If you look at the power board, you'll find tiny adjustable squares we call potentiometers.

They adjust the Voltage listed by it Vs pot witll be easily seen and the Vs test point should be near it too -- if not, just go to the plugs which are clearly labled.

 

The ones I do to guarantee a good picture is the Vs or Va and the Ve -- too much or too little and your picture gets colored "sparklies" in it over time or this funky looking "smear" occurs with the Ve voltage.

 

That's why ALL plasma manufacturers place a white sticker on the plasma panel and list the voltages the panel needs for best picture.

 

You just make sure they are close or right on target, ok?

 

To adjust it, you'll need the voltmeter and the THINNEST flatblade screwdriver you can find.

 

All you do is rotate the adjuster, but beware.....you can't rotate them a Full 360 Degrees, there is only about 270 Deg rotation due to stops on the pot...

 

Don't break that....

 

So go at it....

Customer: replied 4 years ago.
hey...

I am a little worried about this test as the set is working...

I see 2 POT's...on the main P board...one says Vsus next to it, and the other Vd. I assume I am adjusting the Vd pot? I don't see a clear test point...so I sould test the prongs of the P2 plug perhaps? The TV should be on when I do this?

Thanks! sooo close!
Expert:  TV Tech1 replied 4 years ago.

Check BOTH -- they were pre-adjusted at the factory, but they may need a little tweaking....

 

All voltages with knobs/pots/adjusty-thingys should be checked -- and Panasonic is very good about marking the pots so you can match it up with the voltage, which is clearly marked either on a test point OR a connector....

 

You do that ANYTIME you replace that power supply board. What that does is ensure you won't get "sparklies" or Smear /Lag in your plasma's picture.

 

Check them -- they don't have to be Exact, but I try to get it to 0.1 to 0.5 Volts of ideal setting. I have found that pots never seem to let you adjust Exactly, only close to exact.

 

Vd should be listed on one of the plugs going to the SC or the Ssss-uhhhh--SG board?

 

The board on the right side of the cabinet (in service position)

I know that board uses Vd....just can't remember the board's lettering.

 

As for Vsus -- the two large heavy duty wires going to the SC board , and also go to that board I can't remember the letters on, that's your Vsus voltage.

 

Customer: replied 4 years ago.
I tested both two wire honkin cables going to SC and SS for Vsus power...both read 190.3, .3 from the 190 on the tag. The "Vd" voltage on the tag is 144v, but I can not find anything that says Vd or any plug at that voltage. ?
Expert:  TV Tech1 replied 4 years ago.

This picture shows "VDA"...I think that's the actual adjustment, but Vd may be short for VDA....

 

graphic

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I'm screaming your praises!! WOW! I plugged my TV in and bammo! The picture came on bright and beautiful. What a relief! YOU saved me some money and headache. VM United States
< Last | Next >
  • I'm screaming your praises!! WOW! I plugged my TV in and bammo! The picture came on bright and beautiful. What a relief! YOU saved me some money and headache. VM United States
  • I love this site! $9 instead of a repairman or new/used frig can't be beaten. This older woman will worry less now that she knows about this site. Bless you all. Windy USA
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
  • Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
  • Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
 
 
 

Meet The Experts:

 
 
 
  • TV Tech1

    Technician

    Satisfied Customers:

    4800
    30 Years experience. Authorized Warranty servicer.
< Last | Next >
  • http://ww2.justanswer.com/uploads/TV/TVTech1/2013-3-25_625_TECH1Nobanner.64x64.jpg TV Tech1's Avatar

    TV Tech1

    Technician

    Satisfied Customers:

    4800
    30 Years experience. Authorized Warranty servicer.
  • http://ww2.justanswer.com/uploads/OR/OriginalSeadog/2011-7-22_191917_ProfilePicture.64x64.jpg Rod's Avatar

    Rod

    TV & Communications Sys Repair

    Satisfied Customers:

    2354
    FCC Commercial License, Previous owner of Electronics Repair shop, 40+ years in electronic systems.
  • http://ww2.justanswer.com/uploads/benimur/2009-03-29_003401_id_2.jpg Louie's Avatar

    Louie

    Technician

    Satisfied Customers:

    2208
    25+ yrs. experience in the field and 3+ yrs. online, down to component level.
  • http://ww2.justanswer.com/uploads/P0/p0llinate/2011-4-27_174649_tucker.64x64.JPG Nathan's Avatar

    Nathan

    Installer

    Satisfied Customers:

    1683
    Custom home theater installer, authorized dealer top brands.
  • http://ww2.justanswer.com/uploads/ST/steven.benoit/2011-4-1_194735_untitled1.64x64.jpg Steven's Avatar

    Steven

    Technician

    Satisfied Customers:

    1366
    Ma. Master Technician Lic. Authorized Warranty Support.
  • http://ww2.justanswer.com/uploads/IT/ITPeter/2011-5-3_23187_Pete.64x64.JPG Pete's Avatar

    Pete

    Electronic Engineer

    Satisfied Customers:

    1260
    12+ years experience installing and repairing electronics.
  • http://ww2.justanswer.com/uploads/3G/3guk/2011-1-15_132320_D1SC01363.64x64.jpg James's Avatar

    James

    Technician

    Satisfied Customers:

    1154
    AV Service Engineer (4 Years)