Panasonic TX-P42G15

[tw2005]

Re: Panasonic TX-P42G15

Thanks Hombre. Good call on Q702. Although it wasn't shorted I took another closer look at it and there is a small hole in the top.

Q551 was in my list and is shorted between all pins. The others Q501 502 531 521 and 522 I was suspicious of. They are not shorted and no signs of damage but I did just now take resistance readings in-circuit. Based on other threads I understand pins 1-5 and 2-3 should be in Mohms but mine are reading in Kohms or jumping about so I guess I'd better replace them all.

What about ic691? No shorts or damage but I have R707 blown too. How do you test this one?

Hoping for some input from tw2005 too.

Generally the transistors will fail shorted or go low ohms. testing in cct, hard to know what to expect but could show k ohms. Maybe give us actual values and part number with the location as well.

I don't actually know this board off by heart. The next series yes, not this .

[tn245]

Re: Panasonic TX-P42G15

Thanks tw2005

Here's my roadmap (see attachment pdf). Circled in red are components found shorted, burned or exploded. In green are ones I'm not sure about that I'm looking at based on what you and others have found bad on these boards.

They are:
Q441 45G127 - shorted
Q601 RJK6026 - shorted
Q661 RJP6065 - shorted
Q551 CPH5524-TL-E - shorted all pins
Q701 2PD601ART - open, blown up
Q702 MMBTA92 - hole in the top
IC771 TA78L05F-TE12L - shorted
IC464 TC7SH14F - shorted
IC465 TC7SH14F - shorted
IC773 TC7SH14F - shorted
R551 open, burned
R613 open, burned
R707 open, burned
D608 - open, split in two
D618 - short, burned


IC561 VHCT541A - Not sure how to test but seems a common failure?
IC501,521 M81737FP - no shorts, I think possibly they are ok but common failure?
Q501,502,521,522,531 CPH5524-TL-E - readings below:

pins 3-5 on all are shorted together so..
   Q501,502   Q521,522  Q531
1-2 increases  1.7K    increases
1-3 23.5K    25K     increases
1-4 47K     49K     increases
2-3 increases  23K     47K
2-4 increases  47K     47K
3-4 70K     70K     94K

Hombre, what made you replace IC563?

[tw2005]

Re: Panasonic TX-P42G15

Thanks tw2005

pins 3-5 on all are shorted together so..
   Q501,502   Q521,522  Q531
1-2 increases  1.7K    increases
1-3 23.5K    25K     increases
1-4 47K     49K     increases
2-3 increases  23K     47K
2-4 increases  47K     47K
3-4 70K     70K     94K

Something is amiss with your table. pin 2-4 for q501,502 would = 47k ohm

normally I check 1-5, 2-3 and on the 2010 boards i have in cct usually 3 meg or more. So I'm not sure if you are using a datasheet to figure the pins or not. there's 5 pins, #5 does not even get a mention except 3-5 short and that's normal if you look at a datasheet.

[tw2005]

Re: Panasonic TX-P42G15

I would,

search on ebay for any tnpa4782 kits and note the parts supplied.
search within this forum tnpa4752, note any parts reported bad and / or bad after attempted repairs.

search this forum for any model using tnpa4782

TC-50PS14 TC-P50G10 TC-P50S1 TC-P46G10 TC-P46S1 TC-P50G15 TC-P50V10 TC-P46G15 TX-P46G15B

e.g.

here's one example

https://www.badcaps.net/forum/showth...highlight=q604

Thanks tw2005

Here's my roadmap (see attachment pdf). Circled in red are components found shorted, burned or exploded. In green are ones I'm not sure about that I'm looking at based on what you and others have found bad on these boards.

They are:


Q441 45G127 - shorted


Q661 RJP6065 - shorted
IC773 TC7SH14F - shorted
Q701 2PD601ART - open, blown up
Q702 MMBTA92 - hole in the top
R707 open, burned
Q818 2SK3018 (KN) , follow the path of R707 and IC562 could be damaged. hard to test, check p5v resistance

Q551 CPH5524-TL-E - shorted all pins
R551 open, burned
You said IC521 had no shorts, you will if Q551 is 100% short. I'd replace those FET drivers anyway and be suspicious of the rest of that cct like Q451, D451, R451

IC771 TA78L05F-TE12L - shorted
check the schematic and you'll see it provides 5v to several devices any one of which could drag that down. I'd be tempted to just replace everything on that path"


IC464 TC7SH14F - shorted
IC465 TC7SH14F - shorted

Q601 RJK6026 - shorted
R613 open, burned
D608 - open, split in two
D618 - short, burned

again check the cct, I'd be wary of that P-FET, Q604

also wary there are no 2pg011 or the 30g123 mentioned as bad. I would test resistance between the legs(all) they can fail and still have 200 ohms which continuity check will not beep to show short


IC561 VHCT541A - Not sure how to test but seems a common failure?
IC501,521 M81737FP - no shorts, I think possibly they are ok but common failure?
Q501,502,521,522,531 CPH5524-TL-E - readings below:

......................

[tw2005]

Re: Panasonic TX-P42G15

marked what Hombre has mentioned. i think with yours I would assume you're not the first person to attempt repair with R707 blown and so expect more than normal damaged as per what Hombre did with his. if you look at the paths from r707, IC562 & IC691 most likely have taken a hit since it blew apart.
so it'd be a matter of adding what you know is bad to checking what he's done and check that p fet

IC562 I would consider, 561,563 not so sure they would need to be.

[tn245]

Re: Panasonic TX-P42G15

Thanks tw2005. That's all extremely helpful.

Re: CPH5524-TL-E - q501,502 I went back to double check and got 47k pins 2-4 as you said. Then I went to double check Q531, after which I went back to 501&502 and got the increasing readings I reported before. Probably related to other parts of the circuit as I am reading them in-circuit? I will prob replace them all anyway as they are cheap. Was using the pin assignments as you posted.

in-circuit unless mentioned otherwise:
Q604 P-FET reads 9K ohm G-S, open circuit all other combinations
Q401,402,403 2PG011 all read 47K G-E, open all other combinations
Q421,422,423 30G123 also read 47K G-E, open all other combinations
Q451 pulled out of circuit - no shorts or low ohms
D451 tests fine
R451 5.7 ohm
IC691 no shorts or low ohms
Q818 no shorts or low ohms - undamaged

[tw2005]

Re: Panasonic TX-P42G15

Thanks tw2005. That's all extremely helpful.

Re: CPH5524-TL-E - q501,502 I went back to double check and got 47k pins 2-4 as you said. Then I went to double check Q531, after which I went back to 501&502 and got the increasing readings I reported before. Probably related to other parts of the circuit as I am reading them in-circuit? I will prob replace them all anyway as they are cheap. Was using the pin assignments as you posted.

in-circuit unless mentioned otherwise:
Q604 P-FET reads 9K ohm G-S, open circuit all other combinations
Q401,402,403 2PG011 all read 47K G-E, open all other combinations
Q421,422,423 30G123 also read 47K G-E, open all other combinations
Q451 pulled out of circuit - no shorts or low ohms
D451 tests fine
R451 5.7 ohm
IC691 no shorts or low ohms
Q818 no shorts or low ohms - undamaged

I'd encourage you to put Q818 & IC691 on the shopping list watch the package sizes as they are smaller than normal.

[tn245]

Re: Panasonic TX-P42G15

Right, so based on all that, I'm looking to replace:

Q441
Q551,501,502,521,522,531
Q601
Q661
Q701
Q702
Q818
IC464
IC465
IC501,521
IC562
IC691
IC771
IC773
R551
R613
R707
D608
D618

What do you think? Any of the ones I've counted out that you really think I should replace anyway just to be sure?

I will order extra of each just in case as they are cheaper when ordering multiples anyway.

[tn245]

Re: Panasonic TX-P42G15

Which of these would be right for IC691?
http://www.utsource.net/search.aspx?keyWords=TC7SH00FU

[tw2005]

Re: Panasonic TX-P42G15

Which of these would be right for IC691?
http://www.utsource.net/search.aspx?keyWords=TC7SH00FU

The suffix FU dictates the size for toshiba. you can always get Texas Instruments subs for both of those Toshiba logic ICs.
I'd just pick the first on their list.

SN74AHC1G00DCKR is for this one TC7SH00FU, SC70 | 5

http://uk.rs-online.com/web/p/standa...gates/6524136/

SN74AHC1G14DBVR, TC7SH14F SMV/SOT-23 | 5

http://uk.rs-online.com/web/p/schmit...31344442565226

Those AE 5v regs are TA78L05F and are 150ma. most are only 100ma

http://uk.rs-online.com/web/p/buffer...tions/6628516/

[tn245]

Re: Panasonic TX-P42G15

Huge thanks tw2005, I'll get all that stuff ordered and update once I've put it all in. It's going to be a fun soldering job!

[tn245]

Re: Panasonic TX-P42G15

So, I finally got everything soldered in, checked and double checked before installing with buffers disconnected and SC50 jumpered... and..

Something around Q818/702 blew up and now I've got shorts on Q401,402,403,421,422,423 & 661 as well as D865. I guess maybe some of the parts tested I thought were good were failed in some way that wasn't obvious, or I missed something.

I haven't got round to testing all the smaller components yet but I'm thinking to be safe I might just replace everything again as well as the things I missed from Hombre's list the first time.

[tw2005]

Re: Panasonic TX-P42G15

Right, so based on all that, I'm looking to replace:

Q441
Q551,501,502,521,522,531
Q601
Q661
Q701
Q702
Q818
IC464
IC465
IC501,521
IC562
IC691
IC771
IC773
R551
R613
R707
D608
D618

What do you think? Any of the ones I've counted out that you really think I should replace anyway just to be sure?

I will order extra of each just in case as they are cheaper when ordering multiples anyway.

So, I finally got everything soldered in, checked and double checked before installing with buffers disconnected and SC50 jumpered... and..

Something around Q818/702 blew up and now I've got shorts on Q401,402,403,421,422,423 & 661 as well as D865. I guess maybe some of the parts tested I thought were good were failed in some way that wasn't obvious, or I missed something.

I haven't got round to testing all the smaller components yet but I'm thinking to be safe I might just replace everything again as well as the things I missed from Hombre's list the first time.

Just digging up some old TNPA4782 threads, thought I'd just compare since I just fixed 2 of these and the second board seems close to your list.

Q601, RJK6026 shorted_ used STP10NK60ZFP 600V 10A N FET
Q661, RJP6065, shorted_ used RJP63F3A
Q441, 45G127 _ shorted_used 45G128
Q451, 45G127 _ shorted_used 45G128
Q701, MMBTA92
Q702, 2PD601
Q818, 2SK3018 _ used 2N7002
Q551 CPH5524_ shorted
D608, MA8120M, MAZ81200ML 12V 150mW zener(DIODE ZENER 12V 150MW SMINI2) _ open cct_ I had to improvise here and used 1N4742 12V 1W axial lead
D618 RF101L4S 400V 1A shorted
R613 47K was open cct, can not tell in cct if good

IC771,724,725 78L05 _ seemed ok

IC773(bad),564, 464,465 _ TC7SH14F

IC691 TC7SH00FU

IC521 M81707FP _ used M81737FP

Both IC561,562 were shot showing a P5V in resistance of about 500ohms

R521,522 100ohm 5% metal _ burnt out open cct

[Herpana]

Re: Panasonic TX-P42G15

Hi, I all so have TX-P46G15 with six blink errorcode.
There is no swollen caps, burned resistor or transistors. If I detach D20 and D32 ribboncable, powerled stays green. Can't find any schematics no where.

[proman28]

Re: Panasonic TX-P42G15

hello everyone this is my first post i will be compiling few kits for these boards and all you guys thanks for nice tips i am working towards few combination kits i will be putting some good info this post soon as i recieve the parts and confirm that these module can be repaired easily

[Alastair E]

Re: Panasonic TX-P42G15

hello everyone this is my first post i will be compiling few kits for these boards and all you guys thanks for nice tips i am working towards few combination kits i will be putting some good info this post soon as i recieve the parts and confirm that these module can be repaired easily

Hmm--

There's NO such thing as an Easy SC board repair when you're looking at these as well as the other slightly younger aged ones!

Trying to make up a 'cover-all' kit--you might as well list the BOM of the whole board!

Ive done a number of these as well as the 5105, 5081 types and the hideous 5066 boards. Not one had the same set-up of parts faulty as any other of the same type!

Out of curiosity,--How many of these type SC have you repaired...?

[tn245]

Re: Panasonic TX-P42G15

I can't believe it's been more than two years since my last post on this thread and I've still got the TV sitting around waiting to be fixed. I got demoralised on it after repairing and blowing up the SC a couple of times. Am tempted to take another stab at it now as it's been hanging around too long.

At the time I ordered loads of bits from utsource and got quite a few extras as they were cheaper if you order more and take ages to arrive. I hadn't heard of all the fakes by then. I'm suspecting some of my bits might be fakes now.

The main thing I notice is the markings are very faint compared to the originals. Attached is a photo of the igbts I got.

Where are people getting genuine parts from now? Also, is it likely just the igbts that will be fake or have people found the smaller parts fake too? Trying to work out what of the bits I've got will be safe to use. I spent quite a bit of money on all the bits back then.

I seem ohmsupplies has a kit for the 4782 although they seem mixed up on model nos as they have it listed for 30 series panasonics.

[matyka]

Re: Panasonic TX-P42G15

Hello,After I managed to fix my sc board on this set ,is all running only problem is something with the picture .See photos please .
What could cause this problem ?

[tn245]

Re: Panasonic TX-P42G15

For completeness I need to post here to report I finally fixed my tnpa4782. I had switched over to posting about it on this thread by tw2005:
https://www.badcaps.net/forum/showth...451#post823451

PC461 turned out to be bad and I had forgotten to solder R707 back in. That got me to SOS6 instead of 7. Then I found there was a broken trace under IC521 causing missing drive signal to Q451. Read the thread for the full story.

The IGBTs from utsource I posted about before seem to work fine but I was told by another forum member they look to be used pulled parts with new legs soldered on. I guess better than nothing.

[steviewonder]

Re: Panasonic TX-P42G15

Yes,Avoid UTsource at all costs!! They seem to specialise in fake parts...
been there.. done that!.