Panisonic 42inch TCP42S30 not working!!

[Glitcher]

Re: Panisonic 42inch TCP42S30 not working!!

some of the fets are actually in parallel so if one is shorted, both will appear shorted, so youll have to lift the leg to actually figure out which is bad.

Also keep in mind, that not all of them are fets, but some are also diodes which will measure shorted from pins 1 and 3 (this is normal).

What are the part numbers for the ones you found? and can you post a photo of the entire board?

[Hok]

Re: Panisonic 42inch TCP42S30 not working!!

ok just found 4 more - apparently shorted fets, lifted the legs and they won't pass voltage (tried the open gate then test for falling voltage) neither do they have any resistance, so i've either destroyed them or they're destroyed already.... these are Q451, Q441, D621, D622... Still have a short, but only in one direction (red to pin 1 and com to pin 2) other direction reads great

[Hok]

Re: Panisonic 42inch TCP42S30 not working!!

Perhaps only 3 of these igbt were bad - 3 read resistance of 9-12 Ohms, while the fourth reads 0.2 Ohms. nevertheless, still getting a short at SN2

[Hok]

Re: Panisonic 42inch TCP42S30 not working!!

Thanks, Glitcher... Is it possible to test the mosfets that remain without lifting a leg? I did just lift a leg on one common culprit and it's reading 0 ohms now, whereas is was 46K ohms before lifting the leg so perhaps i'm doing something wrong?

[Glitcher]

Re: Panisonic 42inch TCP42S30 not working!!

I just recently repaired a TCP46S30 with an SC board failure, with the usual 3 bad fets. The short between the main connector should be gone when measuring in both directions. If all the bad components are removed, the short should be gone. At least on my model it did, but im not sure if its the same.

[Hok]

Re: Panisonic 42inch TCP42S30 not working!!

Would anyone care to walk me through the troubleshooting of the SN board?
I have removed q401, q402, q421, and q422 from the board. Bit of a pain with a 25 watt iron...
I am still getting a short at SN2 from pin 1 to pin 3 (though I'm not sure i'm doing this right - assume com goes to ground as always i.e.- red to pin 1 and com to pin 3)
However, I am testing other components which are included in the #$# repair kits on ebay and can't be sure if 1) the results are correct, since they are all in circuit and 2) what kind of results i'm looking for and 3) If I remove all failed components without replacing them would the short at SN2 miraculously disappear?

any takers?

[Hok]

Re: Panisonic 42inch TCP42S30 not working!!

Hi folks, complete novice here with the same issue on Panasonic TC-P42S30 set. I am a veteran DIY'er but not very knowledgeable of electronics. However, I'm ready and courageous enough to dive in and give this a shot.

Thanks to tw2005, Tom, and other users on this forum, as well as austech forum and the great training manual that Tom uploaded, I have narrowed down my issue to the SN board.

I would like to continue troubleshooting the board, but I am unable to do so without a bit of help. I hope that some of you might step to my aid...

I believe I have identified 4 bad IGBT's and have lifted their legs, but would like to verify that and continue to test other components on the board if possible. I don't know if I am testing the resistance at SN2 pins properly. With Com lead on pin 1 I get 31k Ohms, but with leads reversed i get a short. Which one should I believe?

And, how should I proceed to test other components on the board? I am trying to test mosfets but am getting varied readings and can't figure out which ones, if any, are bad.

Could it be that the four I found are the only bad parts... (the gates don't close when i try to short drain-gate, so I'm guessing this means they are bad.)

Would love to continue this project, so if anybody could offer a good place to start I'd be very grateful.

[tw2005]

Re: Panisonic 42inch TCP42S30 not working!!

I have tried replacing the power supply board but still has 14 blinks, suggestions?

As what CAPKID mentions, read post 3, check the link out, read my post 6 and check those links.

Check this link out also https://www.badcaps.net/forum/showthread.php?t=30502
as I have additional info regarding 14 blink and solid LED indication. Post 2 and guide in post 3 should be of some use.

Most likeley will be shorted SN or SS boards, not the PSU as you have worked out with a replacement and no change.

14 blink
Shorted F15V developed after the TV is up and running.

Holding the power switch for over 5 seconds after the unit has gone into shut down and it’s in lock mode with the power LED solid red (Note: the LED stays on if the power button is momentarily pressed).

[capkid]

Re: Panisonic 42inch TCP42S30 not working!!

Did you check the link I posted? The original poster had a bad SS. Again, I'd read through that thread and test before assuming that replacing the SS board will solve your problem.

[Waggy]

Re: Panisonic 42inch TCP42S30 not working!!

I have tried replacing the power supply board but still has 14 blinks, suggestions?

[tw2005]

Re: Panisonic 42inch TCP42S30 not working!!

As per CAPKID, Check for shorted Vsus lines on the SN and SS boards. You can get wrong and some weird SOS blinks when there's a dead short on those.

https://www.badcaps.net/forum/showth...RJP30E4&page=2

https://www.badcaps.net/forum/showth...ight=tc-p42s30

https://www.badcaps.net/forum/showth...ight=tc-p42s30

[RJARRRPCGP]

Re: Panisonic 42inch TCP42S30 not working!!

My Panasonic TCP42S30 suddenly turned off when I was watching it. I unplugged it and plugged it back in and still nothing happened, but when I turn it on the red light blinks 14 times then pauses and blinks 14 times again. It also has no picture AND no sound. Help!?

May have been damage from a poco issue. Did you see anything else in the building stop briefly?

[Waggy]

Re: Panisonic 42inch TCP42S30 not working!!

Yes I opened the back. Everything looked fine from what I could see.

[capkid]

Re: Panisonic 42inch TCP42S30 not working!!

Panasonics don't normally have cap issues. Here's a thread for a similar issue:

https://www.badcaps.net/forum/showthread.php?t=23815

I wouldn't jump to the conclusion reached in the thread I provided without doing some checking.

[guyonphone]

Re: Panisonic 42inch TCP42S30 not working!!

Hello Waggy,
Have you opened up the back and checked the power supply for bulging/leaking capacitors, that's where I would start.

[Waggy]

My Panasonic TCP42S30 suddenly turned off when I was watching it. I unplugged it and plugged it back in and still nothing happened, but when I turn it on the red light blinks 14 times then pauses and blinks 14 times again. It also has no picture AND no sound. Help!?