Panasonic TC-P58S2 7 blinks

[gdawg]

Hope I can get some friendly advice. I have repaired numerous Panasonic SC boards and have fixed quite a few Panasonic plasma's . I have got a Panasonic P58S2 with 7 blinks. I have followed the technical guide for this model, but it shows a p42s2 with a combined upper and lower board. The guide shows my model # in it but of course it has the usual SU-SD buffers. The 1st resistance check is with everything connected and my readings are totally different- not shorted but way off from where they should be. I found an SC board on ebay stated tested in a working tv. I get the same readings. This is the part where I am confused. On my original board and the newly purchased board I can jump sc50 with the buffers isolated and the tv turns on and stays on. I can turn the power off and tv turns off. Both the SC and SS board led's are lit. At this point I originally thought the buffers were bad, but they pass the test. I get 2.2 megaohms on pin 1 and 2 of the buffers as per one of the posts here. I was hoping for some advice as these boards are expensive and also hard to find. I don't have a scope, but pretty handy with my Fluke- I replaced the battery just in case. As you know from fixing quite a few SC boards, my soldering skills are pretty good. I know tw2005 and tom66 have posted a lot on Panasonic repairs, so I hope you guys read this. The board #'s are tnpa5173, 5174, and the SC is 5175. I can attach pictures if needed. Hope to hear back- Happy holidays to all!!!

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

I would do the full resistance check as per the g20,25 series handbook as the values and pinouts are the same . If they match then this could be a bad panel but the guide suggests bad SU is more likely than bad panel.

have you checked everything is connected correctly on the sd/su e.g. vfg bolts, interconnecting ribbon etc.

also in the G20/25 book it suggests you can isolate either board suggesting isolating the SU first as it's higher on the list for possible 7 blink. If doing this I would remove it completely from the TV, sc50 will still need to be jumped.

You can the same for the SD, re-install the Su and remove the SD but read the guide first as I have never done this so I'm only going to repaeat what has already been written.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Thanks, I did do the full resistance check-I think there are 3 steps. I will do the isolation per the G guide. I don't remember, but I think I already did that. I sure hope its not a bad panel. I guess I will have a lot of spare parts if it is. Thanks I will post my results but it might take awhile.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Hope this post isn't too late. I put this project on the back burner. I hope TW2005 reads this and can shed some light. If I remove the buffers and jump sc50 , the tv powers on and stays on untill I shut it off. I bought a SU board from SJ and checked resistance and checked all the pins for shorts and everything checks ok. If I install either buffer and jump SC50, I get 7 blinks. That's either SU only connected, SD only connected and tried both connected with out the jumper, I get 7 blinks. I removed the ribbon off the SC board and got 6 blinks. That was with the buffers removed. That tells me the A board is ok. MY question is, can the SC still be bad even if it stays on with the buffers removed. I tested some of the test points on the SC board. Of course I have VSUS at 204v, Vad I had a weird read of -36 v, I also checked Vscan and dont remember the reading. The 4 Vfg pads had -80v on each one. Any thoughts. I really think the SC is bad, but I am stumped. I did order a replacement SC board, but get same results. Thanks for any input.

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

Hope this post isn't too late. I put this project on the back burner. I hope TW2005 reads this and can shed some light. If I remove the buffers and jump sc50 , the tv powers on and stays on untill I shut it off. I bought a SU board from SJ and checked resistance and checked all the pins for shorts and everything checks ok. If I install either buffer and jump SC50, I get 7 blinks. That's either SU only connected, SD only connected and tried both connected with out the jumper, I get 7 blinks. I removed the ribbon off the SC board and got 6 blinks. That was with the buffers removed. That tells me the A board is ok. MY question is, can the SC still be bad even if it stays on with the buffers removed. I tested some of the test points on the SC board. Of course I have VSUS at 204v, Vad I had a weird read of -36 v, I also checked Vscan and dont remember the reading. The 4 Vfg pads had -80v on each one. Any thoughts. I really think the SC is bad, but I am stumped. I did order a replacement SC board, but get same results. Thanks for any input.

Running just one buffer with SC 50 jumped may not work although the guides suggest you can. I tried that on a 2011 model i=and all I got was 7 blinks.

I would think if the SC with sc50 jumpered and the sd/su removed the TV stays on then the SC is ok. Since you say you've got another SC and it's doing the same then that reinforces it's not the SC.

What are you getting with the resistance tests for each board sd/su? Vfo, Vf5v, Vscn-f

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

I will ck tonight when I get home, so I will let you know. Thanks for the reply, this is driving me crazy. I have fixed quite a few Panny's but this one is tough. I will list my readings tomorrow.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Well TW2005, I guess I answered my own question. I used your chart you had posted( I think it was yours) and here are the results. I will have to say, the training guide just has you check a few of the pins, which is a little misleading.
SD
1-1.99m
2-219.6k
3-OL
4-OL
5-7.68m
6-7.72m
7-OL
8-7.72m
9-OL
Is there a problem with 5,6, 8 being high

SU
1-OL
2-2.2m
3-OL
4-219.8k
5-OL
6-OL
7-OL
8-3.1 ohm
9-OL
Well I guess it's obvious there is a short in the 5v_f on pin 8

Anything replaceable on pin 8 or is it one of the chips. I wish I would have measured them all, but because the training guide just had you measure a few. If the SC boards still light the led and the tv stays on, do you think the SC board is ok. Thanks for your time on this. I feel kinda dumb, I didn't check all pins. So I know I need an SU board unless there is a repair for it and not sure about the high readings on the SD. They seemed to climb as I held the probes on the pins. Thanks for your input. I like Panny's to fix cause they are challenging for me.

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

yeah, I think if that pin 8 is a definite 3 ohms it's a goner. No I have no answer to repairable or not , I think you'll have to go with another SU board and hope that's it.

So there's a few thing s bouncing around in my head.

This Su board with the 3 ohms is that the SJ board?

What readings did your original boards have? That's all 3 not just Vfo.

I'd check IC724 on the SC boards and make sure it's resistances match what the training guide has as this feeds that 5V-f line that is shorted.

I have had a 5081 board which one of those was shorted between in & out so intead of 15V in 5v out it was the full 15v and bth the sd/su were shot on that TV on the 5v-f lines .

i just mention it just in case. It's equivalent to a 78M05 reg

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Thanks for the tip. I did not check all 3 readings as I was following the training guide that just shows to check 1 pin. I believe that was the SJ board so I will check on the return. Do you think the SD board is ok with the readings I got? I guess high readings are better than low. I will check the ic you recommended on both SC boards. I can check that with the board powered up,right? Or should I check with my MM. Both SC boards enable the tv to turn on with no codes. It's the old story,what came first, the chicken or the egg!! Thanks TW2005, you are awesome and this Forum rocks. I will post my results, but might take awhile.

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

Thanks for the tip. I did not check all 3 readings as I was following the training guide that just shows to check 1 pin. I believe that was the SJ board so I will check on the return. Do you think the SD board is ok with the readings I got? I guess high readings are better than low. I will check the ic you recommended on both SC boards. I can check that with the board powered up,right? Or should I check with my MM. Both SC boards enable the tv to turn on with no codes. It's the old story,what came first, the chicken or the egg!! Thanks TW2005, you are awesome and this Forum rocks. I will post my results, but might take awhile.

you could check the output with it bypassed and running but safer to just check resistance between the tab(gnd) and pin 3 (output) 2.6k with the buffers disconnected. And just a quick check between 1 & 3 is not a short, 1-gnd I think may be in meg ohms I forget now.

The g20 series guide has expanded resistance tests on the buffers . Same design , the buffers just have heatsinks in these otherwise they're the same boards. S2 is just a slightly cheaper version on the G

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Just an update, I did check both SC boards and the reading at IC724 are identical. No short between pin 1&3 And ground to one tab is in mega ohms and ground to the other tab is in hundreds of k ohms. So my next step is to find a SU board and from what I understand, I can install good SU board by itself and not jump SC50 and tv should turn on and stay on. Correct?? Of course I will certainly do a full check on the SU board when I find one. Thanks TW2005. Your knowledge in Panasonic plasma's is greatly appreciated and I have learned so much reading all the posts. Let me know if I am thinking correctly. I am 63 years old and still learning!!!!

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Just a correction on last post. Gnd to pin 3 was in kohms not hundreds of kohms. Did not post the exact reading but I know it was not shorted. Thanks

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

Just an update, I did check both SC boards and the reading at IC724 are identical. No short between pin 1&3 And ground to one tab is in mega ohms and ground to the other tab is in hundreds of k ohms. So my next step is to find a SU board and from what I understand, I can install good SU board by itself and not jump SC50 and tv should turn on and stay on. Correct?? Of course I will certainly do a full check on the SU board when I find one. Thanks TW2005. Your knowledge in Panasonic plasma's is greatly appreciated and I have learned so much reading all the posts. Let me know if I am thinking correctly. I am 63 years old and still learning!!!!

No, you'll have to jump sc50. any remoal of a buffer board opens the cct and triggers 7 blinks.

It may or may not work even though it says you can run one board. On my 2011 TV it failed to work. it either needed both boards out and sc50 or both in but when I went 1 board sc 50 it failed. I did not persist with it as I kenw the SU was shot, just tried it for curiosity but sometimes best not to play too long and create more work blowing a SC board.

It's running now with a new Su.

[Alastair E]

Re: Panasonic TC-P58S2 7 blinks

If Either Buffer-Board is Out--Then it'll need SC50 linked to run.

--The boards are all interlocked, removal of either buffer without SC50 will give a 7-blinker.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Thanks for the info. I always used the jumper when using only one board. I was just having trouble diagnosing. I tried it with SC jumpered and without. Now I know to for sure jump it if one buffer is removed. Once I get the SU board, I will report.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Does any one know if you have to have the panel ribbons attached to the buffer to test it after power up. In other words, if I just use the SU board and jump SC50 and not fasten the ribbons to the buffer, will it throw a 7 blink code or not?

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

Does any one know if you have to have the panel ribbons attached to the buffer to test it after power up. In other words, if I just use the SU board and jump SC50 and not fasten the ribbons to the buffer, will it throw a 7 blink code or not?

Good question, never tried it. I have on a LG 50PJ250 had all ribbons disconnected to test boards as the panel was cracked and got away unscathed.

Not really prepared to stick my neck out just in case.

Are you thinking of a possible dud panel?

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

I sure hope not. I have tried mine either way and always get the 7 blinks. I ran the SD board by itself last night and jumped SC50. If you recall the SD board I have has some high readings over 7mohms on some of the pins. It still did the 7 blink code. My plan of attack is to wait till I have the SU board, check all the pins to make sure its good and hopefully install it and not get 7 blinks. I guess if that happens, then I will assume the high readings on the SD board will not work and will have to replace the SD board also. Panasonic plasma's always seem to kick my butt. But I should say I have fixed quite a few, including rebuilding a few of the SC boards that have about 9,000 components on them. I will report when I get the SU board . I hope its a positive report!!

[tw2005]

Re: Panasonic TC-P58S2 7 blinks

I sure hope not. I have tried mine either way and always get the 7 blinks. I ran the SD board by itself last night and jumped SC50. If you recall the SD board I have has some high readings over 7mohms on some of the pins. It still did the 7 blink code. My plan of attack is to wait till I have the SU board, check all the pins to make sure its good and hopefully install it and not get 7 blinks. I guess if that happens, then I will assume the high readings on the SD board will not work and will have to replace the SD board also. Panasonic plasma's always seem to kick my butt. But I should say I have fixed quite a few, including rebuilding a few of the SC boards that have about 9,000 components on them. I will report when I get the SU board . I hope its a positive report!!

I've seen figures like that on the SD, I'd just get a SU , check the readings , if good fit both boards, fire it up.

[gdawg]

Re: Panasonic TC-P58S2 7 blinks

Just wanted to report my findings. SUCCESS!!!! I bought an SU from ebay from a seller that said good board from a broken screen. I thoroughly expected to ck resistance and have it be bad on arrival. But all readings checked normal. And as tw2005 said, Put both buffers in and fire it up and it came up and running. I even got all the ribbons on the first try. I did the scrolling bar anti retention and every thing good. I probably should not have gotten the SC board but never hurts to have spare parts. I paid $65.00 for the buffer and lucky I found a good one. I hope its not speaking too early but I am pretty happy right now. Thanks to all on this forum and a special thanks to tw2005 for sticking with it. I do have a TC-P55gt31 with the same issue. I replaced the shorted fet's on the SC board. and it fires with out the buffers. I know I have a shorted SU and they are really hard to find. TNPA 5340. It has 1 shorted chip and I successfully removed it with out damaging traces. I may attempt replacing it for the experience. I don't know if should drink heavily before the attempt and just blame it on the alcohol if it doesn't work or try it sober!!!