Panasonic sc tnpa5081 rebuild

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

solved staff!!
I reball in ddr3 memory of the motherboard and she returned to work

Nice job, interesting because I have a mainboard from a 50U20 which is the cheap version of this TV, sounds like same issue just lose picture and control of TV, running with green LED. I've replaced the main board but still have the old one. I shall keep it for an experiment one day and try your memory reball / flow? What are the chip numbers you worked on?

[leeroy012]

Re: Panasonic sc tnpa5081 rebuild

Can you tell me what chips are on sc board TNPA5081 in q421 and q403 places?

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Can you tell me what chips are on sc board TNPA5081 in q421 and q403 places?

you know if you read this thread you'd find out or search.

anyway DG502LW DG402LW by panasonic

D16451 RF101L4S 400V 1A
D16482 RFN25TM4SW
D16702 MA2J11100L 80v 100ma
Q16452 GT45G128
IC16521 M81737FP
IC15771 78L05L, TA78L05F
IC16773 TC7SH14F, marking HA, Schmitt NOT
Q16402 DG3D5020
Q16403 DG3D5020
Q16421 DG3D4020
Q16422 DG3D4020
Q16521 CPH5524-TL-E
Q16551 CPH5524-TL-E
Q16647 2SK3018T106,2n7002
Q16661 RJP63F3A
Q16701 MMBTA92
Q16702 2PD601ART,215, 2SD0601A0L
Q16818 2SK3018T106,2n7002
R16521 100 OHM,J,1/8W 1
R16522 100 OHM,J,1/8W 1
R16707 3.9KOHM,J,1/8W 1

IC16561 TC74VHC541FK
IC16562 TC74VHC541FK

[mngopher22]

Re: Panasonic sc tnpa5081 rebuild

tw2005 I just had my tv's TNPA board go bad. Here is my first pass diagnosis.

Part Status Manuf Notes

Q661 SHORTED RJP63F3A
Q401 SHORTED DG502LW
Q402 OK DG502LW 580V breakdown
Q403 OPEN DG502LW
D401 OK F50ALW
D402 OK F50ALW

Q421 SHORT DG402RP
Q422 SHORT DG402RP
Q423 SHORT DG402RP
D421 OK FUS20T4S 430V 20A
Q601 OK JK60


Q452 SHORT 45G128
D481 OK RFUS20
D482 SHORT RFUS20


R551 OPEN
R452 OPEN
R521 OPEN
R522 OK
Q551 SHORT PNP/NPN totem buffer
IC521 BAD M81737FP Gate Driver
IC562 OK Buffer

I have pulled out all of the bad parts I could find. I then powered up the 5V, 15V, 16V_F, 15V_F, and 5V_F individually. You can power individual circuits with a nice current limited power supply. This helps in diagnosing whats wrong. I will detail this process in my next post. I believe now that those power up with no shorts, I don't have any bad parts left in the circuit. Now I need to source some replacements and begin to repopulate the board.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

IC16563 C0JBAB000916 IC 1 , marking c14, INVERTER IC = TC74VHC14FK VSSOP Toshiba

UTSOURCE has them, also direct from panasonic parts stockists

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

you know if you read this thread you'd find out or search.

anyway DG502LW DG402LW by panasonic

D16451 RF101L4S 400V 1A
D16482 RFN25TM4SW
D16702 MA2J11100L 80v 100ma
Q16452 GT45G128
IC16521 M81737FP
IC15771 78L05L, TA78L05F
IC16773 TC7SH14F, marking HA, Schmitt NOT
Q16402 DG3D5020
Q16403 DG3D5020
Q16421 DG3D4020
Q16422 DG3D4020
Q16521 CPH5524-TL-E
Q16551 CPH5524-TL-E
Q16647 2SK3018T106,2n7002
Q16661 RJP63F3A
Q16701 MMBTA92
Q16702 2PD601ART,215, 2SD0601A0L
Q16818 2SK3018T106,2n7002
R16521 100 OHM,J,1/8W 1
R16522 100 OHM,J,1/8W 1
R16707 3.9KOHM,J,1/8W 1

IC16561 TC74VHC541FK
IC16562 TC74VHC541FK

this is not necessarily a "do this" guaranteed list, 30f125 IGBTs x 2 not mentioned but can be assured at least 1 will be bad majority of the time, I'd replace both, may see 200-300ohms across legs which is bad, may miss these if you rely on continuity check alone.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

tw2005 I just had my tv's TNPA board go bad. Here is my first pass diagnosis.

Part Status Manuf Notes

Q661 SHORTED RJP63F3A
Q401 SHORTED DG502LW
Q402 OK DG502LW 580V breakdown
Q403 OPEN DG502LW
D401 OK F50ALW
D402 OK F50ALW

Q421 SHORT DG402RP
Q422 SHORT DG402RP
Q423 SHORT DG402RP
D421 OK FUS20T4S 430V 20A
Q601 OK JK60


Q452 SHORT 45G128
D481 OK RFUS20
D482 SHORT RFUS20


R551 OPEN
R452 OPEN
R521 OPEN
R522 OK
Q551 SHORT PNP/NPN totem buffer
IC521 BAD M81737FP Gate Driver
IC562 OK Buffer

I have pulled out all of the bad parts I could find. I then powered up the 5V, 15V, 16V_F, 15V_F, and 5V_F individually. You can power individual circuits with a nice current limited power supply. This helps in diagnosing whats wrong. I will detail this process in my next post. I believe now that those power up with no shorts, I don't have any bad parts left in the circuit. Now I need to source some replacements and begin to repopulate the board.

Not optimistic with your list. must be a 54" model. But i don't see IC771,773, Q701,702, 818, or any 30F125 IGBTs. Also D451 can short

[myfastgti]

Re: Panasonic sc tnpa5081 rebuild

this is not necessarily a "do this" guaranteed list, 30f125 IGBTs x 2 not mentioned but can be assured at least 1 will be bad majority of the time, I'd replace both, may see 200-300ohms across legs which is bad, may miss these if you rely on continuity check alone.

Thanks tw2005 for helping me identifying the faulty 30f125. Too bad the diode continuity shows both good but resistance check actually confirms if they're good or not. I my case both were around 264 ohms

Have already placed an order with Utsource last week.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Thanks tw2005 for helping me identifying the faulty 30f125. Too bad the diode continuity shows both good but resistance check actually confirms if they're good or not. I my case both were around 264 ohms

Have already placed an order with Utsource last week.

If that was in cct then when pulled 1 may test ok as they're paired just like the DG402 & 502 IGBTs but for those usually both will be bad.

I'd replace both but you may need to redo ic773, q701,702,818 and obviously whatever else has shorted. Sometimes you're better off replacing everything associated that drives Q661.

If you go to the schematic there a 3.9k resistor that can blow with a failed attempt on Q661 blowing again. Check D451 too that's another that can be missed.

Once you get one right, the next one will be easier. I always do ic773, q701,702,818 regardless of whether I think they're good or not.

Chances are ic771 is ok, they don't always go when ic773 shorts

[myfastgti]

Re: Panasonic sc tnpa5081 rebuild

IC 771 is good and I did received IC 773 from Digikey last week, still waiting for 30f125. Since I choose USPS, it'll be at least 2 weeks before I can retest the board.

The r707 3.9 k Ohm was good in both attempts but Q701 didn't survive. I believe there is a 4.7 k ohm resistor across both fets which was giving me reading of less than 100 ohm. Will see once I've all the parts

One last question I wanted to ask is do I need to worry about Q521 CPH5524-TL-E and Q551 CPH5524-TL-E. They seems good as the resistance check confirms according to your previous post.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Off the top of my head they often survive. I have not had to replace these except maybe one board. Once you have the FET driver, the 45G128 etc that are bad around there removed, if you check resistance across the opposing pins at both ends I think it may show 2-3 megohms,

That's width ways not length way as you look at the device. On the side that has 3 legs,end to end on that same side will show short .

[myfastgti]

Re: Panasonic sc tnpa5081 rebuild

3rd attempt failed again with a load pop and back to square one.

One thing I want to bring to attention of everyone is I received 16 pieces of 30f125, out of which 2 pieces have resistance of 27k and 300k compared to rest which showed between 1.7 and 2.0 M Ohm. Not sure if you guys run into these while ordering from Utsource.



Here's the list of components I replaced

D16451
D16482
Q16452
D16702
IC16521
IC16691
IC16724
IC16771
IC16773
PC16461
Q16402
Q16403
Q16421
Q16422
Q16521
Q16551
Q16621
Q16622
Q16647
Q16661
Q16701
Q16702
Q16818
R16452
R16551

In the next attempt I'll be replacing IC16792, IC16561 and IC16562 since this only ones IC's didn't replaced

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

3rd attempt failed again with a load pop and back to square one.

One thing I want to bring to attention of everyone is I received 16 pieces of 30f125, out of which 2 pieces have resistance of 27k and 300k compared to rest which showed between 1.7 and 2.0 M Ohm. Not sure if you guys run into these while ordering from Utsource.



Here's the list of components I replaced

D16451
D16482
Q16452
D16702
IC16521
IC16691
IC16724
IC16771
IC16773
PC16461
Q16402
Q16403
Q16421
Q16422
Q16521
Q16551
Q16621
Q16622
Q16647
Q16661
Q16701
Q16702
Q16818
R16452
R16551

In the next attempt I'll be replacing IC16792, IC16561 and IC16562 since this only ones IC's didn't replaced

I'll try and digest this soon but my hopes are low , really expect a win this time, failed attempts and additional damage i suspect = near impossible(for me) to work out. i only got my 5 attempt board going with the aid of a good board to check against and even then there was a fair amount of luck. This is such a shame, it's the misssed 30F125 s that started this roller coaster.

I understand the drive to succeed though. If a broken one pops up on ebay that may be cheaper and easier to ry again. there were 5 not long ago but they got snapped rreal fAST BY SOMEONE WHO REPAIRS THEM i SUSPECT.

Dammit, CAPS lock

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

@ MYFASTGTI

Mate I'm out of ideas, must be something that does not normally fail maybe after a failed repair.

One thing i need to know, when you you powerup the SC is that with buffers connected or without and SC50 jumpered.

Asking just in case you have the buffers connected and they are shorted? Have you checked the buffers?

[myfastgti]

Re: Panasonic sc tnpa5081 rebuild

@ MYFASTGTI

Mate I'm out of ideas, must be something that does not normally fail maybe after a failed repair.

One thing i need to know, when you you powerup the SC is that with buffers connected or without and SC50 jumpered.

Asking just in case you have the buffers connected and they are shorted? Have you checked the buffers?

All tests were conducted without buffer boards/SC50 shorted. I also checked SU/SD boards and they tested good before I started working on SC board.

Have you run into bad 30f125 before ? Out of 16 peices I ordered 2 were having resistance of 300 kohm. I'm checked these fresh out of box as they arrived. I've a feeling some of the other IGBT's might have been DOA and would be the reason for failures.

Have been really busy and haven't started working on removing the failed components from SC board yet. Also someone of the Craigslist is selling cracked Panasonic TV with similar model, I'm going to buy and compare the readings of all the replaced components and will post results.

One thing I noticed that the readings of boards with MIP390's are way too different than boards with MIP391. A resistance check of MIP390 is around kohm but a resistance check of MIP391 is in mohm with ground.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

All tests were conducted without buffer boards/SC50 shorted. I also checked SU/SD boards and they tested good before I started working on SC board.

Have you run into bad 30f125 before ? Out of 16 peices I ordered 2 were having resistance of 300 kohm. I'm checked these fresh out of box as they arrived. I've a feeling some of the other IGBT's might have been DOA and would be the reason for failures.

Have been really busy and haven't started working on removing the failed components from SC board yet. Also someone of the Craigslist is selling cracked Panasonic TV with similar model, I'm going to buy and compare the readings of all the replaced components and will post results.

One thing I noticed that the readings of boards with MIP390's are way too different than boards with MIP391. A resistance check of MIP390 is around kohm but a resistance check of MIP391 is in mohm with ground.

Never touched one or replaced But I think someone here has and was faulty. If you tell me what you get on each pin and referrence I could dig out a board to see. With cracked panel TV, I've found the buffer dies but so far from 3 TVs SC have survived and SD always shot. Unless of course the panel was cracked and power never applied.

Have not had issues yet with the bits but I'm always suspiscious

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

I have a quick question what DMM are you using for these measurements? Once you report back I will let you know why I am asking.

I am currently working on a board out of a 54" TV I will report back my repair after I receive my parts on Monday.

Thanks,
Dean

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

I have a quick question what DMM are you using for these measurements? Once you report back I will let you know why I am asking.

I am currently working on a board out of a 54" TV I will report back my repair after I receive my parts on Monday.

Thanks,
Dean

I have an old fluke 75

[dolivas27]

Re: Panasonic sc tnpa5081 rebuild

Ok I need a little help with this one.

Ok so I picked up this unit cheap to try and repair it. Model # TC-P54G25

The unit has the 7 blink code and of course the problem is the SC board. or so I thought

TNPA5081 Rebuild Notes
1st Repair Attempt
Replaced = Not sure if it was Bad

IC501 - Replaced
IC521 - Replaced
Q421 - Shorted
Q422 - Shorted
Q423 - Shorted
Q401 - Shorted
Q402 - Shorted
Q403 - Shorted
Q452 - Shorted
Q661 - Shorted
D481 - Shorted
Q818 - Replaced
IC771 - Replaced
IC774 - Replaced
IC691 - Replaced
IC773 - Replaced
Q702 - Replaced
Q521 - Replaced
Q551 - Shorted
Q660 - Shorted
Q701 - Replaced

2nd Repair Attempt
I retested everything again like I was starting the repair from the beginning and here is what I found. I was looking at the flow chart and Q608 jumped out at me as a possible problem part. I'm wondering if others that have failed did not have a bad Q608 it was causing the Q661 to blow every time! I would not have found this bad part if I did not remove it from the circuit. What I found was the part was leaky when tested. I replaced it a reinstalled the board SUCCESS THE BOARD NOW WORKS!!!!

D642 - Shorted
Q661 - Shorted
Q608 - Leaky

Ok now it's time to connect the buffer boards and fire it up. Yes I measured the buffer boards and they looked good NO shorts. Being All excited I have it fixed I connect everything and plug it in and BANG a loud POP now a 10 Blink code! Test for shorts again and now the Vsus is dead shorted! Remove the SC2 connector and turn the set back on and have the 7 Blink code again! SC BLOWN AGIAN!!!!!


3rd Repair Attempt
Once again retest everything like I was starting the repair from the beginning. This is what I found blown I had to order PC461 from China so I had to wait 2 weeks for it to get here. Thinking I must have measured or missed a shorted buffer board I ordered both buffer boards while I waited for the PC461 to get here. I receive the buffers and tested them they look fine as do the originals?



D642 - Shorted
D641 - Shorted
Q661 - Shorted
Q402 - Shorted
Q421 - Shorted
Q422 - Shorted
Q423 - Shorted
D642 - Shorted
Q661 - Shorted
PC461 - Shorted

PC461 came in and I installed it and retested the board everything looks good. Reinstall it in the set and once again tested it without the buffer boards and the jumper installed in SC50. Everything powers up fine no blink codes!!!! Power cycled it several time to make sure it was fine. Reconnect the new buffer boards take some measurements to make sure everything looks good it does so decide to proceed with a power up. BANG LOUD POP and the SC BLOWS AGAIN!!!!

What am I missing could the Panel be bad? I checked it to Chassis ground and do not see any shorts. Could the SS board be causing this? but if that was case would it not blow with the buffers removed and the SC50 jumper installed? Going to rebuild the SC again but before I test it again with the buffers installed I need some help to figure out what is causing it to BLOW.

[tw2005]

Re: Panasonic sc tnpa5081 rebuild

Ok I need a little help with this one.

Ok so I picked up this unit cheap to try and repair it. Model # TC-P54G25

The unit has the 7 blink code and of course the problem is the SC board. or so I thought

TNPA5081 Rebuild Notes
1st Repair Attempt
Replaced = Not sure if it was Bad

IC501 - Replaced
IC521 - Replaced
Q421 - Shorted
Q422 - Shorted
Q423 - Shorted
Q401 - Shorted
Q402 - Shorted
Q403 - Shorted
Q452 - Shorted
Q661 - Shorted
D481 - Shorted
Q818 - Replaced
IC771 - Replaced
IC774 - Replaced
IC691 - Replaced
IC773 - Replaced
Q702 - Replaced
Q521 - Replaced
Q551 - Shorted
Q660 - Shorted
Q701 - Replaced

2nd Repair Attempt
I retested everything again like I was starting the repair from the beginning and here is what I found. I was looking at the flow chart and Q608 jumped out at me as a possible problem part. I'm wondering if others that have failed did not have a bad Q608 it was causing the Q661 to blow every time! I would not have found this bad part if I did not remove it from the circuit. What I found was the part was leaky when tested. I replaced it a reinstalled the board SUCCESS THE BOARD NOW WORKS!!!!

D642 - Shorted
Q661 - Shorted
Q608 - Leaky

Ok now it's time to connect the buffer boards and fire it up. Yes I measured the buffer boards and they looked good NO shorts. Being All excited I have it fixed I connect everything and plug it in and BANG a loud POP now a 10 Blink code! Test for shorts again and now the Vsus is dead shorted! Remove the SC2 connector and turn the set back on and have the 7 Blink code again! SC BLOWN AGIAN!!!!!


3rd Repair Attempt
Once again retest everything like I was starting the repair from the beginning. This is what I found blown I had to order PC461 from China so I had to wait 2 weeks for it to get here. Thinking I must have measured or missed a shorted buffer board I ordered both buffer boards while I waited for the PC461 to get here. I receive the buffers and tested them they look fine as do the originals?



D642 - Shorted
D641 - Shorted
Q661 - Shorted
Q402 - Shorted
Q421 - Shorted
Q422 - Shorted
Q423 - Shorted
D642 - Shorted
Q661 - Shorted
PC461 - Shorted

PC461 came in and I installed it and retested the board everything looks good. Reinstall it in the set and once again tested it without the buffer boards and the jumper installed in SC50. Everything powers up fine no blink codes!!!! Power cycled it several time to make sure it was fine. Reconnect the new buffer boards take some measurements to make sure everything looks good it does so decide to proceed with a power up. BANG LOUD POP and the SC BLOWS AGAIN!!!!

What am I missing could the Panel be bad? I checked it to Chassis ground and do not see any shorts. Could the SS board be causing this? but if that was case would it not blow with the buffers removed and the SC50 jumper installed? Going to rebuild the SC again but before I test it again with the buffers installed I need some help to figure out what is causing it to BLOW.

I've got no idea I'm afraid as I have not been in this situation. For me at least if it passes without the buffers, it's worked and kept working. Can't see it being the SS as it's not directly tied to it like the HD models.

Really weird 2 sets of buffers doing the same. Is everything in right, all bolts for the SC and teh sd/su? All ribons in straight on the sd/su, ribbon between the sd/su connected?

what pins on which buffers and what resistances did you get?

what suffixes are on the buffer boards?