Panasonic TX-P42U10E 7 Blinks

[Moreno83]

Hey guys.

Got this nice looking panasonic tv thats blinking 7 times on startup.
At the moment im just gathering information so i can work on this tv tonight.
With removing SC board its blinking 6 times.

After reading some threads including Shinjo's thread , I found out that most of the time the problem is the SC board or buffer boards. Is this tv one of the models that had "bad screws" ?

Its a 2010 model.

SC board = TNFA-4829
PS = ETX2MM747MF

Hope that someone can give me some advice what to test first?






*Pictures tonight , im at work.

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Hey guys.

Got this nice looking panasonic tv thats blinking 7 times on startup.
At the moment im just gathering information so i can work on this tv tonight.
With removing SC board its blinking 6 times.

After reading some threads including Shinjo's thread , I found out that most of the time the problem is the SC board or buffer boards. Is this tv one of the models that had "bad screws" ?

Its a 2010 model.

SC board = TNFA-4829
PS = ETX2MM747MF

Hope that someone can give me some advice what to test first?






*Pictures tonight , im at work.

No, but like most Panasonic plasmas the SC quits sooner or later. Must be very early 2010, really it should be part of the 2009 model line up.

what are you like at component level repair? Repaired any SC boards?

not sure how easy these boards are to get or could be pricey.

basic first step is to do the SD/SU boards bypass.

basically remove the 4 Vfg bolts from the SD/SU, disconnect the 3 connectors from sc to buffers.
short the 2 pins on the sc at SC50, power on and see if it stays on.

alternatively, check SC2 for short cct or a visual may find FET driver ic burnt or SMD diodes burnt

or

remove the SC and start checking the IGBTs for short cct

Start with Q661,660, 601. if nothing then continue with the rest

How many hours before you get home?

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Hi TW2005 ,

Im "good" at repairing/soldering the boards so that wont be a problem. ( removing and replacing components ).
I just found a similar thread wich you replied to with the same answer so when i get home ill try the bypass on the SC50 connector first.
Do i only need to remove the screws or remove the buffer boards from the SC board?

I think i have another pair of these smaller bufferboards. The mainboard looks almost identical to the 3D models that came out in 2011 ( GT20 ).

Indeed , the panel sticker says late 2009.

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Hi TW2005 ,

Im "good" at repairing/soldering the boards so that wont be a problem. ( removing and replacing components ).
I just found a similar thread wich you replied to with the same answer so when i get home ill try the bypass on the SC50 connector first.
Do i only need to remove the screws or remove the buffer boards from the SC board?

I think i have another pair of these smaller bufferboards. The mainboard looks almost identical to the 3D models that came out in 2011 ( GT20 ).

Indeed , the panel sticker says late 2009.

I don't think any 2010 (Gt20) will help, signals from that along SC20 are different. I just did a 2009 50G15 and was hoping I could use my 2010 V20 to plug in to just for a SC board test with no buffers but can not be done.

I'll check the schematics but not optimistic, besides i think this will be a SC repair

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

I'll try the test first to see if it stays on or not. I will be home in 6 hours....

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

I'll try the test first to see if it stays on or not. I will be home in 6 hours....

yeah, I don't think we're going to be online at the same time much

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Sometimes I think if the SC is suspect, checking for shorted parts is a safer option just in case continually powering the Sc up does more damage. I notice on the 4782 boards there's a diode that shorts and burns long enough to burn the board and track out.

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

basic first step is to do the SD/SU boards bypass.

basically remove the 4 Vfg bolts from the SD/SU,

disconnect the 3 connectors from sc to buffers.

short the 2 pins on the sc at SC50, power on and see if it stays on.

.

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Ok , i will remove the board first and check for viscible damage. If the board looks ok , ill do the test.

Those fets/diodes , are they on more SC boards? ( same kind )

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Ok , i will remove the board first and check for viscible damage. If the board looks ok , ill do the test.

Those fets/diodes , are they on more SC boards? ( same kind )

generally of the same generation so 2009 boards but I used 2010 model parts and got mine running

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

I have not checked all parts like the large IGBTs which you can clearly see but the small stuff will be correct.

R606 10KOHM 0.25W
R696 2.2ohm 5W
Q661 RJP6065
D618 RF101L4S
D619 RF101L4S
D865 RF101L4S
Q441 45G127
Q451 45G127
D608 MAZ81200ML (12V 150mW) SSMINI2
Q401 2PG011
Q402 2PG011
Q403 2PG011
Q501 CPH5524
Q502 CPH5524
Q521 CPH5524
Q522 CPH5524
Q421 30G123
Q422 30G123
Q423 30G123
Q601 RJK6026
Q660 RJK6026
Q701 MMBTA92
Q702 2PD601ART
Q818 2SK3018
IC724 TC7SH14F
IC725 TC7SH14F
IC771 TC7SH14F
IC501 M81707FP
IC521 M81707FP
PC461 PS9817A-2
PC601 PS2701A-1
R506 10 OHM 0.25w , ERJT06J100V
R507 10 OHM 0.25w , ERJT06J100V
R551 10 OHM 0.25w , ERJT06J100V
IC464 TC7SH14F
IC465 TC7SH14F
IC773 TC7SH14F

depending on how much surrounding damage is at ic521, these can get taken out whenthat driver shorts out
ic561,562 tc74vhct541a

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Thanks for all the help tw2005!! Will try it when i get home and see if i can fix the problem!

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Thanks for all the help tw2005!! Will try it when i get home and see if i can fix the problem!

Well if have a load of parts maybe, but lets see what you find first.

of course could be buffers but SC is up there.

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Ok i did what you said.

Disconnected the bufferboards from the SC board and used the SC50 jumper.
The tv stays on but no picture.

This means 1 or 2 buffer boards are bad?

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Tested both buffer boards and the lower buffer board is short on 2 pins. Rest is all good.

Is this the chip thats bad? Or can it be a different part on the print?

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Tested both buffer boards and the lower buffer board is short on 2 pins. Rest is all good.

Is this the chip thats bad? Or can it be a different part on the print?

Well how ironic. I had a feeling after I'd done all that work it'd be buffer just to prove a point since I was assuming the worst.

Are you thinking of trying to replace just the buffer IC? have you done that before? watch out for the sealant as that is also under that chip makes it hard to get off but I had a go at removing these for fun and I found using acetone helped with removing the sealant making it separate a bit easier.


Not sure what you're asking whther to confirm it's the SD or you want to narrow it down to the IC. you'd have to show us the pins shorted but you should be able to trace the tracks to what IC

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Haha , i was suspecting the SC board also!!

Its the lower buffer board. the chip is located on the bottom of the board. ( connector 3 from the left ).
Only 2 pins are short , the first and almost the last 1.

Not sure if i want to repair it , would need a chip first! Cant take 1 from a other SU boar d right?
Costs of 1 board is just 20$ …..

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Haha , i was suspecting the SC board also!!

Its the lower buffer board. the chip is located on the bottom of the board. ( connector 3 from the left ).
Only 2 pins are short , the first and almost the last 1.

Not sure if i want to repair it , would need a chip first! Cant take 1 from a other SU boar d right?
Costs of 1 board is just 20$ …..

Get the board, keep the dead one for another day. I've been praticing on a damaged 5090 board, just getting good at it. I use generous mounts of acetone and pick away at the silicone. get a a sharp fine blade and cut the legs against the casing, don't go too deep there's tracks below. then more acetone and grab the ic twisting back and forth.

should just pop off. then get the rest of that goo off , using something like a toot pick to work it, carefully desolder the remaining legs.

I already posted these on ricosavy thread as these buffer boards are starting to run out.

The chips are not cheap maybe $4-7 each for me. adds up fast if all 6 - 8 are blown on a board and not having the correct gear or experience.

1 or 2 chips I'd have a go at.

[Moreno83]

Re: Panasonic TX-P42U10E 7 Blinks

Thx for the update! This looks like a AS15 chip wich i have replaced many times.

I tried to turn the tv on without the ribbon cable for that defective chip but still 7 blinks.....
Think that the tv only works with all chips intact...right?

Question is , do i need the EXACT same chip? Or can i use a different one? Got many SU boards.

[tw2005]

Re: Panasonic TX-P42U10E 7 Blinks

Thx for the update! This looks like a AS15 chip wich i have replaced many times.

I tried to turn the tv on without the ribbon cable for that defective chip but still 7 blinks.....
Think that the tv only works with all chips intact...right?

Question is , do i need the EXACT same chip? Or can i use a different one? Got many SU boards.

The fault is on the board , not the panel so no that won't work. can you use different chips? maybe.Tom seems to think there's some interchange, maybe another chip for FHD panel and a panasonic, I don't know. Not my thing.

I'd expect buffers from any 2009 FHD will have the same chip.

I guess AS15 has 4 sides, but 48 pins , TQFP-48 9 x 9 mm, compared to 128 pin?