Confusion with Panasonic A boards

[dcapper]

Re: Confusion with Panasonic A boards

If I unplug the YSUS and ZSUS, I still get no power out of the top of the power supply.

The top left and right in the picture.

[tw2005]

Re: Confusion with Panasonic A boards

If I unplug the YSUS and ZSUS, I still get no power out of the top of the power supply.

The top left and right in the picture.

That's a concern, you're measuring as you powerup? so give me the sequence of events with those disconnected.

You plug Tv in, standby led? turn on, relay clicks?, what does LED do? normal startup?, faults with blinks? How many?

[tw2005]

Re: Confusion with Panasonic A boards

Another thing that can be done is disconnect 3 white ribbons from the A board, disconnect SN2, SS11, P35 at the PSU this feeds down to the C boards. Have all the power cables connected to the A.

Startup, hopefully it will turn on normally and if you probe the PSU all volatges should be present.

If it still blinks, turnoff and swapover your original A board( apart from the broken ribbon connector, was anything else damaged or missing removed?)
Repeat.

If the original is not usable for this then swap over the PSU with the new A and repeat.

Note everything you can and post.

[dcapper]

Re: Confusion with Panasonic A boards

Sorry I took so long to reply. I disconnected the SS and the SN boards I get 190v for a brief second on both sides of the power supply at the top of the power supply board. But when I disconnect either the SS or the SN, I get no voltage. The power looks like it goes from the power supply to the SS then to the SN but with another connector from the power supply to the SN. I removed the SS and metered 6 gates and all of them are completely shorted. It looks like someone tried to replace them. I am considering buying a SS board but worried I'll have to buy the SN too. It looks like the power supply is ok. I'm running out of boards to replace but now I'm so far into this thing I might as well replace everything and at least break even. Lucky I paid practically nothing for it.
The old power supply was butchered. Missing parts and bad solder joints.

EDIT: I disconnected all the connectors you suggested I remove and I get power at the top power supply points that stay on.

[tw2005]

Re: Confusion with Panasonic A boards

Ok, so why i mentioned in post 11 about the SS.

So at this stage you now know PSU and A board are good.

Normally shorted SS will trigger SOS4 but still could be the 10 blink..

How much do you know about this TV? So now you're saying the PSU had missing parts as well as the A board, plus SS shorted.

Either whoever worked on this had no idea or I'm a little suspicious with the number of bad items making me wonder if this set has been used as a donor for a couple of TVs and all the bad boards put into one TV?

We still don't know if the panel is good either.

Normally on the SS when it fails, it's 4 IGBT transistors, the other 2 maybe diodes and showing short at this stage because of the others.

As far as power goes, you have Vsus entering SS11 & SN2. SS3 to SN3 is the ERC(energy recovery cct)

So if you check resistance across SS11 with the cable removed it's shorted?

You say if either SS or SN connected, no voltage? that's still a concern as that suggests the SN is also shorted at SN2?

I'd still like to know what blinks you are getting though as each item is disconnected.

we might have to resistance check everything to try and get an idea how much else may be dead.

Since I have the same TV i can get an idea from that. it powers up with no SOS but i have maldischarge and have halted spending more money on it.

My situation is a little similar as originally had 4 blinks bad SS, but underneath that fault once cleared, i ended up with 1 blink A board and somehow did a IGBT on the ERC on the SN, then had a bad C board and now runs with bad image.

Try leaving the SS11 removed , have evrything else connected and recheck to see if Vsus comes up briefly.

If not, checking resistance across SN2

[dcapper]

Re: Confusion with Panasonic A boards

I was given the tv. Either the guy was a butcher or it really took a hard hit. The power supply was replaced and we know its working. The old A board was a mess, it was missing chips. I bought a new A board. The SS board must be faulty too. Q101, Q102, Q001, Q002, D001, D021, Q021, and Q022 are all shorted. SS11 connection is shorted between Vsus and GND, but ok from Vsus to +15vc, and from +15vc to GND. If I have the power connector from SS3 to SN3 connected I get a short circuit on SN2. But if I remove the cable from SN3 I get 7.9k ohms to start and it keeps climbing.

If I disconnect P35 and all the ribbon cables as well as SS3 and SS11, but leave SN2 connected, the power does not stay up. The only way the power supply stays on is if I disconnect all the ribbon cables, P2 and P11.

I never once have gotten a flash of light from the screen.

Also if I have everything disconnected except P35 but have one ribbon cable connected to the left bottom buffer board and the power stays up. The rest if connected one by one goes to 190v then drops to 0.

I think you are correct. This tv is a mess of faulty parts. I'm thinking I have a bad SS board, a bad right bottom buffer board, and maybe a bad SN board (the verdict is out on this board, due to the fact is that I have resistance at SN2).


EDIT: I just metered some of the transistors on the SN board. Q661, Q421, Q402, and Q401 are all shorted, even with the panel ribbon cables disconnected. So basically I need a new SN, SS, and the bottom right buffer board, while praying the panel is good. $130 for all of them on Shopjimmy. I wish there was a way to test the panel without power. I'm already into this tv for $160. So after all said and done I'll be in $300. I can sell if for that I guess, if I can get it running.

[tw2005]

Re: Confusion with Panasonic A boards

If I disconnect P35 and all the ribbon cables as well as SS3 and SS11, but leave SN2 connected, the power does not stay up. The only way the power supply stays on is if I disconnect all the ribbon cables, P2 and P11..

What blink code generated?

If I have the power connector from SS3 to SN3 connected I get a short circuit on SN2. But if I remove the cable from SN3 I get 7.9k ohms to start and it keeps climbing..

So we're talking resistance across SN2? Did you get a final reading?

EDIT: I just metered some of the transistors on the SN board. Q661, Q421, Q402, and Q401 are all shorted, even with the panel ribbon cables disconnected...

So shorted across any 2 legs on the transistor? Pretty conclusive then,

I never once have gotten a flash of light from the screen....

You won't

Also if I have everything disconnected except P35 but have one ribbon cable connected to the left bottom buffer board and the power stays up. The rest if connected one by one goes to 190v then drops to 0. ....

Now I'm nervous and a little confused.

Removing the 3 white ribbons from the A board removes a shutdown SOS from anything else unless it's generated by the A or P boards.

So which ribbons? (A21,SN20)(A33,C11)(A34,C21

If it's these, that would be expected. What was the blink code? SOS8? SOS8 is triggered by the SS routes back to the A via C2 board ribbon.

Or is it the panel ribbons into the C boards?

The last thing you want to do is mess around with those bottom ribbons. there's an integral heatsink and chip embedded on the film. If they get damaged it's all over for the panel.

What makes you think you need a C2 board ?

[dcapper]

Re: Confusion with Panasonic A boards

The power supply only has the AC in, P6, P7, with the ribbon cable connected to C1. I get 190v on the power supply and no blink codes when I try to power it up.

When I say ribbon cables I mean the white ones to A21, A33, and A34 on the A board. I only have A33 (goes to C1) hooked up and full power on the power supply but no blink codes. When I plug in A34 (goes to C2) and get power for a second on the power supply then nothing but get 6 blink codes. So I guess the C2 board is good. I was just think it might be faulty cause the power supply shuts down immediately.

So it would appear I do need an SN and SS board since they are both shorted out.

[tw2005]

Re: Confusion with Panasonic A boards

The power supply only has the AC in, P6, P7, with the ribbon cable connected to C1. I get 190v on the power supply and no blink codes when I try to power it up.

When I say ribbon cables I mean the ones to A21, A33, and A34 on the A board. I only have A33 (goes to C1) hooked up and full power on the power supply but no blink codes. When I plug in A34 (goes to C2) and get power for a second on the power supply then nothing but get 6 blink codes. So I guess the C2 board is good. I was just think it might be faulty cause the power supply shuts down immediately.

So it would appear I do need an SN and SS board since they are both shorted out.

Well it sounds like you know how to use a meter. If you found dead short on some of the transistors on the SN whether SN2 is short or not then it's bad.

You're correct, SOS6. I forgot about SN20 removed so that's normal. With SN20 connected get SOS7.

Not real sure how much you can check on the C boards except the 3.3V resistance and even then probably does not prove good or bad.

[tw2005]

Re: Confusion with Panasonic A boards

Payless components is another alternative for parts. For $124 + freight you get SN,SS,C1,C2. I'd enquire about the combined freight.

How much saving with no C board?

[tw2005]

Re: Confusion with Panasonic A boards

Still curious to know what blinks you had with just SS11 removed and everything else hooked up.

[dcapper]

Re: Confusion with Panasonic A boards

I'm in Canada so I pay a little more for shipping. Without the C1 and C2 boards I would pay $112.34 shipped. They have no stock on the C1 but it's $21.83. There is a seller on Amazon which is payless (I looked after) that has both C1 and C2 that would ship to me for $25.00

I just went on Payless components. They want alot more than Shop Jimmy for the TNPA5066.

TNPA5066 Shop Jimmy $66.16, Payless $75.14

The TNPA5072 are the same price.

The TNPA5075 and 5076 are way cheaper with payless.

[tw2005]

Re: Confusion with Panasonic A boards

I get 6 with SS11 off, 6 with SS11 and SS3 off,

[dcapper]

Re: Confusion with Panasonic A boards

With everything on except for SS11, I get 10 blinks.

With everything connected except for SN2 and SS11 I get 7 blinks.

With everything connected except for SS3 and SS11 I get 10 blinks.

With all the shorts on my SS and SN boards, I would assume they are faulty. I guess I could order the C1 and C2 boards. They are only $25 for the pair shipped.

[tw2005]

Re: Confusion with Panasonic A boards

I'm in Canada so I pay a little more for shipping. Without the C1 and C2 boards I would pay $112.34 shipped. They have no stock on the C1 but it's $21.83. There is a seller on Amazon that has both C1 and C2 that would ship to me for $25.00

I only mention Payless from previous experience and most of his stuff is from new damaged in transit Tvs. he has a pair of C boards around $13. I've use Sj too but freight to this side of the world is expensive although it's a premium service.

payless will ship a board to me here at about a third, I don't mind waiting to save $$

I'm only thinking going in this deep get everything but if postage is cheap either way won't matter I guess.

Sure hope this has a happy ending.

Like i mentioned earlier, similar to my predicament. I still have mine in hope I find a solution.

don't forget there's different revisions of the boards. There are some equivalents for the 42" plus SANYO had a model with the same panel and I think on the SS they have a different panel connector but does the same job.

[dcapper]

Re: Confusion with Panasonic A boards

I'm going to start with the SN and SS and go from there.

[tw2005]

Re: Confusion with Panasonic A boards

With everything on except for SS11, I get 10 blinks.

With everything connected except for SN2 and SS11 I get 7 blinks.

With everything connected except for SS3 and SS11 I get 10 blinks.

With all the shorts on my SS and SN boards, I would assume they are faulty. I guess I could order the C1 and C2 boards. They are only $25 for the pair shipped.

So 10 blinks is from the SN and gets detected before the shorted vsus which normaly would be 4 blink.

Did you ever check the resistance on the 5v and 15v lines on the SN like you said you would? that's the post i created an image with some test points for you.

I'm thinking one of those may have an issue.

I only ask because that info can be handy to have in these posts for future troubleshooters.

Not every failure will be the same.

[tw2005]

Re: Confusion with Panasonic A boards

I'm in Canada so I pay a little more for shipping. Without the C1 and C2 boards I would pay $112.34 shipped. They have no stock on the C1 but it's $21.83. There is a seller on Amazon which is payless (I looked after) that has both C1 and C2 that would ship to me for $25.00

I just went on Payless components. They want alot more than Shop Jimmy for the TNPA5066.

TNPA5066 Shop Jimmy $66.16, Payless $75.14

The TNPA5072 are the same price.

The TNPA5075 and 5076 are way cheaper with payless.

I'd send Will at Payless a polite message and see if he can do a deal and price beat SJ or the reverse SJ may price beat him.

Hell, maybe even mention some mad Australian gave a referral on a forum and ask if he still has his opening promotion going. he's on ebay but the website is fairly new.

Of course you should decide on your own gut feeling but so far neither SJ or payless have let me down.

I have done this with SJ and saved .

[dcapper]

Re: Confusion with Panasonic A boards

SS3 - all 3 pins are shorted
SS11 - 15v to GND is acting like a diode
SS11 - Vsus to GND is shorted
SS11 - Vsus to 15v is acting like a diode
SN3 - pins 3-5 is shorted
SN3 - pins 1-5 is acting like a diode
SN3 - pins 1-3 is acting like a diode

Hope those numbers help. With all those transistors shorted on the SN and SS, the numbers must be off.

[tw2005]

Re: Confusion with Panasonic A boards

SS3 - all 3 pins are shorted
SS11 - 15v to GND is acting like a diode
SS11 - Vsus to GND is shorted
SS11 - Vsus to 15v is acting like a diode
SN3 - pins 3-5 is shorted
SN3 - pins 1-5 is acting like a diode
SN3 - pins 1-3 is acting like a diode

Hope those numbers help. With all those transistors shorted on the SN and SS, the numbers must be off.

SN3 pins 3,5 are the same(gnd), I think from memory resistance is around 54K between 1-3,5