Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

[lowbrow]

Hi all,

My TC-P50s30 started to give the 7 blinks. I opened the back and did a resistance test across the two pin connector (power) on the SC board. This showed basically 0 Ohms (Based upon the reading I've done on the site). I suspect that means I have several shorts on my SC board. I'm just curious as to the best method to diagnose which components will need to be replaced. Can they be tested with the multimeter while still attached to the board? Which Pins should I be reading across, what readings should I see, ect.

I ordered a repair kit from Shop Jimmy. Just hoping I don't have more shorted components than I receive.

[tw2005]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

same board in my TV

https://www.badcaps.net/forum/showthread.php?t=42613

got away with replacing 4 x 30f131 transistors

[ricosavy]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

You also need to make sure that you buffer boards are not shorted.

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Thanks folks,

Any idea the best way to test the adjacent buffer boards? Or just repair and test the SC, then connect the two buffers and see if it works?

[Alastair E]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

You need to check the buffers for shorts, as a duff buffer can kill an SC.....

[ricosavy]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

0nce you repair sc board you can install it and are sure there are no shorts .You can do a resistance check from tpsc1 to ground set meter to ohms you should not have any continuity if you have like 11 ohms one of buffer boards is shorted.To figure out which one disconect the connector from buffer board to sc.Disconnect top buffer first and check resistance if no resistance then top is bad.If still resistance disconnect bottom and reconnect top and recheck resistance gone bad lower buffer.Here picture to where you can check resistance.

if you have the buffers boards off you can check them like this for shorts
In video

https://m.youtube.com/watch?v=k0EZHBr4dMQ

[tw2005]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Well, SJ certainly moving with the times moving towards repair as salvaged boards dry up.

https://www.youtube.com/watch?v=UmJYQ7oEbKg

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

^ Great video, are those typically the components on the board that go bad?

[tw2005]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

^ Great video, are those typically the components on the board that go bad?

as far as i know but i would check all of the board for any other IGBTs shorted and those larger SMD diodes.

like i said before, i just needed the 4 transistors

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Update:
Things were looking good for like... 30 seconds.

Replaced the 4 transistors, and the resistance readings on the small resistors looked better, and was getting an appropriate reading on the main terminal. Plugged it in (did NOT connect the buffers) jumpered it and the TV powered on and showed some sporadic purple lines in the black... SUCCESS!

Connected the buffers and got a 0 ohm reading from the ground screws to tpsc 1... I mistook that as no continuity... I should have unplugged them both and tested them individually... but alas, I did not.

I plugged it in... and 7 blinks. I'm pretty sure I blew my SC again. Readings on my small resistors are back to being a bit high, and I'm not getting a great reading across my main terminal.

Turns out my top buffer is shorted. Had I have taken the time to individually test them, I would have seen a 20 ohm resistance reading on it. So... I'm off to buy a SU board, and likely replace the 4 transistors again.

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Also, are the buffer boards the same for the p50ST30 as they are for the p50S30? Look similar, part numbers are very similar.

[tw2005]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Also, are the buffer boards the same for the p50ST30 as they are for the p50S30? Look similar, part numbers are very similar.

you'll have to go over the whole board and not assume just the same parts failed

never tried but i did have a close look at the buffer pictures and ccts and made a comment here.

https://www.badcaps.net/forum/showth...npa5337&page=2

from what i saw only difference was adding heatsinks

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Bit of an update, and looking for a little more advice.

I replaced the 4 transistors again and tested the SC without the buffer boards and it powered on. I bought a new SU (TNPA5336A6 out of a UK TX-P50VT30B rather than a TNPA5336AM). It looked the same but with the addition of heatsinks.

I tested and installed the SU and get picture, but the portion controlled by the new-to-me SU has some horizontal black lines going through in places (Picture attached).

Just wondering - would this be because of an incompatible SU? Or perhaps there are a few more components on the SC I need to replace. I double and triple checked the ribbon cable connections, even wiggled them a bit with it powered on, made no difference.

[tw2005]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Bit of an update, and looking for a little more advice.

I replaced the 4 transistors again and tested the SC without the buffer boards and it powered on. I bought a new SU (TNPA5336A6 out of a UK TX-P50VT30B rather than a TNPA5336AM). It looked the same but with the addition of heatsinks.

I tested and installed the SU and get picture, but the portion controlled by the new-to-me SU has some horizontal black lines going through in places (Picture attached).

Just wondering - would this be because of an incompatible SU? Or perhaps there are a few more components on the SC I need to replace. I double and triple checked the ribbon cable connections, even wiggled them a bit with it powered on, made no difference.

Good progress but whatever you do , DON'T try manipulating these ribbons with it on especially if misaligned because if they happen to short they will blow the SC. I've read a few cases now of people doing this including a repair shop.

I'm going with poor ribbon connection.

If you have a can of air, may be an idea to blow out the socket just in case there's something in there on the contacts and like wise inspect the ribbon contacts.

When these are seated, they go in then with a little more effort you can feel them wedge. we're talking bees dick. Grab either side of the ribbon close to th econnector so it does not flex and push perfectly straight and parallel.

Before you try this though, can you post a very clear close up of the SU ribbons. Often you can tell if not right looking at the markers in comparison with the ribbons that are not giving trouble.

We may be able to spot a problem.

You only need to adjust the ribbon that lines up with the problem area.

failing this could be suspect buffer but the norm with this is ribbon alignment

[lowbrow]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

^^ Thanks TW!

You were spot on. Even though the ribbon cables appeared to be fully, and evenly, seated - they were not. It took a bit more pressure than I was comfortable using on ribbon cables, but there was a noticeable further click on 2 - 3 of the cables. Plugged in and powered back on to a perfect picture!

Thanks again for the help, and I hope this thread can help more people!

[Newbie62]

Re: Panasonic Viera tc-p50s30 7 Blinks Troubleshooting

Thanks folks,

Any idea the best way to test the adjacent buffer boards? Or just repair and test the SC, then connect the two buffers and see if it works?

TNPA5336AM & TNPA5337 BUFFER BOARD TESTING:

https://www.youtube.com/watch?v=k0EZHBr4dMQ