TH-P50G15A - 6 Blinks- Bad TNPA4782

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

I did not do Q701 nor Q702, they tested ok. I should probably have done those as well.
I also realized I had a couple resistors that were bad that I didn't replace. At least they were bad after I tested the board so I am not 100% sure. I also realized I had some bad solder joints on one of the IC chips. I need to order more stuff before I can do anything else. But a lot of the large transistors on the heat sinks need to be replaced again, and a couple of the surface mounted diodes need to be replaced as well.
I am going to start again from scratch and just reorder everything and redo it all and go over board on the replacing aka I am replacing everything ha.
Will update once the parts get in and hopefully have the board running.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Did you put a RJP3034 in for Q661?? Q701,702 i would have just replaced, they don't always fail shorted.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Board got plugged in, I made sure to take the buffers out first, and I didn't even do the bypass, I wanted to see what the blinking code would have been with just the SC board plugged in as is. I heard not a pop, but a loud click almost, and i got a lot of shorts on the transistors I replaced. Will post back with damage report later today for general info and hopefully I will find what caused everything to go bad again. And a last update, but I decided to replace the IC 521 just in case as well. and IC 773.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Ok so here is a quick recap of what I have replaced so far, and I also want to point out that every single one of these was tested out of circuit and was faulty except for one of the IC's and one of the surface mount transistors, because I wasn't 100 percent sure how to test them but honestly I think that they were not needed to be replaced.

Q441 45G127
Q423 30G123
Q422 30G123
Q421 30G123
Q401 2PG011
Q402 2PG011
Q601 RJK6026
Q622 RJP3034
Q621 RJP3034
Q661 RJP3034

D618 8896
D865 8896

Q551 CPH5524
IC464 TC75H14F
IC465 TC75H14F

these last 2 are the ones I don't think needed to be replaced.
Q818 25K3018
IC561 T541A

I checked a lot of the other parts and all were good, so I didn't replace them such as:

IC771
IC724
IC725
IC564
IC521
Q876
Q647
IC691
Q701
Q702
D808

Also my board is the AB version, I don't know if that makes much of a difference. I am going to recheck the resistors right now before plugging it in, but is there anything else I should check just in case before?
Also I did not replace the IC521 because it looked fine. But if it turns out that the IC is bad, could it damage stuff on the rest of the board or will it just not turn on? If it might damage some of the stuff I replaced then I definitely would replace it, if not I would rather test it first and then replace it if it turns out the board won't power on.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Perfect, thank you for that info.
I am assuming that for the other IC's the differences in names is not going to actually be a difference in their performance?

So you guys didn't replace the transistor at Q604, I am assuming it will be ok for me to not replace it as well correct?

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

this should look familiar

http://www.utsource.net/ic-datasheet...L-1398603.html

optos are by NEC and part number is on the chip

you have 0.7 at the pads because you have a diod across it( the tiny smd 12v zener)

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Ok IC's now. These seemed a little easier to find.

IC464 low mid TC7SH14F Found that one no problem
IC564 Top left near SC50 TC7SH14F thats the same as the IC464, so all good to go
IC691 upper mid TC7SH00FU This one has 2 choices, TC7SH00FU(T5LFT) Encapsulation:SOT-353, and TC7SH00FU Encapsulation:SOT-353
IC563 Bottom left HB1496K CRDT Yall said this one was not bad on yours, and my IC561 and IC562 seem to be registering ok readings, so what do you think on this, should I actually get it?

IC771 Low mid 78L05 that one is the same as IC724 and IC725
IC724, 725 top mid 78L05 This one I found about 20 variations or so. Below are the ones that I think would work on the board. I left most of the others out of the way.
NJM78L05UA Encapsulation:S OT-89,3 - TERMINAL POSTIVE VOLTAGE REGULATOR
MC78L05ABP Encapsulation:T O-92,
LM78L05ACMX Encapsulation:S OP8L
LM78L05ACZ Encapsulation:T O-92,3-Terminal Positive Regulators
78L05L Encapsulation:S OT
AN78L05M Encapsulation:S OT-89
L78L05ACUTR Encapsulation:S OT89
And the list goes on for this. So what do you guys think? Most of these listings don't have pictures.

Now that we got all the IC's, comes the Opto, I don't think we ever listed the actual part numbers for these. I would like to buy the
PC461, I know that my PC601 is bad since I can see physical burning on it, and PC603 is giving me some similar readings as 601 is. Would you know the part numbers for these? I am assuming 601 and 603 are the exact same.

One last comment, is that the transistor Q604 I ended up removing, and here are the readings I get on the board with it out of circuit.
red lead on G black on S I get 0.704V any other combination I get OL no matter what. This is all on diode mode by the way. Not sure what that tells us.

Thank you once again for all the help.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Thanks for all of the info, super helpful.
I will be ordering the above today, and tomorrow I might have a couple extra questions regarding 1 or two of the IC's and making sure I am getting the proper ones, and possibly an extra question about the PC601 part number, and PC461 PS9817A-2 is difficult to find, no ebay sellers, and it seems like UTsource does not have it available in stock, but digikey might have it available.
Thanks for everything, I will write again tomorrow once I get back to the shop in front of the board.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

http://www.utsource.net/search.aspx?keyWords=CPH5524

http://www.utsource.net/ic-datasheet...T-4071444.html

2sk3018 - This is the tricky one and I'm yet to get the correct size as there are 2 packages and the OEM is the smaller one. It is possible to get the larger size to fit if you're delicate with the legs and just ever so slightly bend them closer together it can be soldered in to make contact.

The OEM is marking KN but i have ordered against that and it was the large one marked KL (I think)

large- http://www.utsource.net/ic-datasheet...8-1234159.html

most likely large, http://www.utsource.net/ic-datasheet...N-4052939.html

This should be correct but again the package description is SOT323
http://www.utsource.net/ic-datasheet...06-824384.html

I have attached the datsheet, that's exactly the same KN and package UMT3, 2sk3018T106 but i have found this with another item with UT that you get an item that's the same but different package.

e.g. RFN25TM4SW & FN25TM4SW are the same diode but the R means the legs are pre-bent in the reverse direction. I've ordered the R and got the other which is a challenge straightening the legs then re bending in the opposite direction which quite often the leg will crack or break off at the fold.

some things you just have to work with as it's hard finding some parts or expensive.

Note that there is a sweet spot with the qty ordered. Go low or single and it get's expensive. It's obvious they have a min $ of $1 / item if less than 5.

So with those small transistors above you get 4 for $4 or 51 for $5.10. Sure you can work out what best suits but the repair can blow out quickly but if you're into this or intend doing more boards the unit cost per board can be very low if you can get good enough to knock these off first time.

I can knock off a 5081 for about $7-10 in bits because I ordered in bulk the bits that commonly go .

Don't forget there's some diodes that fail, RF101L4S

PC461, is probably ok but you can get from UT. pin 1 is the white dot and 5-8 is Vcc - gnd which if any of the other items feed by ic771 are shorted will be low.

I think it's PS9817A-2,have a look. the -2 is important as it has 2 channels there are -1

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

TW2005, you have been super helpful, and I appreciate it. I do apologize if I am making you repeat yourself, there are 8 pages on this thread, so I am fairly confident I might be at some points asking redundant questions that may have already been answered. I will try my best to go through the posts again before asking more questions.

Before I buy these parts, UTsource has a few variations of them, and I would like to make sure that I am buying the correct parts. The following are the listings that I have in my shopping cart. Can anyone confirm that these are indeed the correct parts.

Q551: 2 options, the CPH5524-TL-E SOT23-5, and the CPH5524-TL-E Encapsulation:SOT153. Which one should I go with?

IC561, IC562: T541A Encapsulation:SMD-20 Straight forward, one option on this one.

Q701: 2 options, MMBTA92LT1G Encapsulation:SOT23, High Voltage Transistors PNP Silicon, and SEMICONDUCTOR MMBTA92LT1G FNFP which do I need?

Q702: 3 options, 2PD601AR, 2PD601AR/ZR, and 2PD601ART version. Which one should I go with?

Q818: There are 3 versions, 2sk3018, 2sk3018KN, and 2sk3018T106. Which do I need?

Thank you for the help on this.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Yes, once I removed Q551 the Q451 was no longer shorted. Perfect, and thank you for that tip. I also have purchased IC521 and am about to instal it in, however I do not have a Q551 available to replace it, I do want to make sure that I am correct on this, but CPH5524 is the proper replacement for it correct?

As for the Q876 Q647 Q701 Q702 Q818 transistors, how would I check them to know if they are working properly? I am assuming Diode mode, but what kind of readings should I be looking for with which lead on which pin?
Can anyone help me with this??

I usually just bell them out for shorts , but, not everything shorts.
pretty sure I'm repeating myself , but Q701 Q702 Q818 I would replace

Q876 I would leave, at worst it will just cause a blink code but will not damage anything as it's in the detection cct.

Q647, IC461 I'm not sure if they're likely suspects, I know I was clutching at straws and did them but on my second board, never touched them.

sometimes it's more efficient to replace than to try and work out if they're good and make an error.

With IC562, if r521,522 are open cct from high voltage back feeding from IC521 then it's a good chance although Vcc-gnd on ic562 is ok that it could be damaged.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Yes, once I removed Q551 the Q451 was no longer shorted. Perfect, and thank you for that tip. I also have purchased IC521 and am about to instal it in, however I do not have a Q551 available to replace it, I do want to make sure that I am correct on this, but CPH5524 is the proper replacement for it correct?

As for the Q876 Q647 Q701 Q702 Q818 transistors, how would I check them to know if they are working properly? I am assuming Diode mode, but what kind of readings should I be looking for with which lead on which pin?
Can anyone help me with this??

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

tw2005

I had a chance to re-read every post and have a better understanding of this board now. Some of the info given earlier about certain bad components was wrong due to certain components shorting out others. Here is what I have replaced so far.

D618, and D865 located on the top left near Q622

Q661 Q621 Q622
Q601 Q401 Q402
Q421 Q422 Q423
Q441

Q451 registers a short between G and E. However it registers a short between those points even with the transistor out of circuit. I have checked D451 and get .455v and OL. I have checked R451 and get 5.6 ohms. Not sure what could be causing this one to do this.
I have replaced all the above, and now every component that is screwed into a heat sink is good to go, and every single larger surface mounted diode is also measuring good.

I have checked IC561 and IC562 and am getting 10 Mega homs between pin 10 and 20 and slowly the ohms decrease. So those should be good.

I checked R521 and R522, they measured about 49Kohms so I think they need replacement.

For the following, what measurements should I get:
Q876 Q647 Q701 Q702 Q818

Q551 I don't know how to measure it, all I can tell you is that the side with 3 pins are all shorted to one another.
Q604 has D and G shorted with it in circuit, I have not taken it out yet. I will update on this.

For the following I have no idea how to measure:
IC521 IC771 IC464 IC465 IC691 IC724 IC725 IC773 IC564

R613 and R869 measure at 42Kohms,
Zener diode at D608 measure good .706 and OL

Now to the Opto, I think that PC601 might be bad but I don't know how to test it. PC461 you mentioned how to test it, but I have no idea what pin is pin 5 and which pin is pin 6 and 7 and so on. How do I know which pin is which? I have tried 4 different scenarios with pin 1 being on each end, and none of the times could I get the same numbers as you did, so I think mine might be bad not sure.

I know I am throwing a lot at a time, and also requesting a lot of information, but I have browsed through this post several times, and got as much info as I could without losing my mind.
Thanks in a advance for the help.

-Nick

The answer to this

Q451 registers a short between G and E. However it registers a short between those points even with the transistor out of circuit. I have checked D451 and get .455v and OL. I have checked R451 and get 5.6 ohms. Not sure what could be causing this one to do this.

I feel is answered by this

Q551 I don't know how to measure it, all I can tell you is that the side with 3 pins are all shorted to one another.

Replace Q551 & IC521. once Q551 is off, check those shorted q451 points, expect that will clear.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

tw2005

I had a chance to re-read every post and have a better understanding of this board now. Some of the info given earlier about certain bad components was wrong due to certain components shorting out others. Here is what I have replaced so far.

D618, and D865 located on the top left near Q622

Q661 Q621 Q622
Q601 Q401 Q402
Q421 Q422 Q423
Q441

Q451 registers a short between G and E. However it registers a short between those points even with the transistor out of circuit. I have checked D451 and get .455v and OL. I have checked R451 and get 5.6 ohms. Not sure what could be causing this one to do this.
I have replaced all the above, and now every component that is screwed into a heat sink is good to go, and every single larger surface mounted diode is also measuring good.

I have checked IC561 and IC562 and am getting 10 Mega homs between pin 10 and 20 and slowly the ohms decrease. So those should be good.

I checked R521 and R522, they measured about 49Kohms so I think they need replacement.

For the following, what measurements should I get:
Q876 Q647 Q701 Q702 Q818

Q551 I don't know how to measure it, all I can tell you is that the side with 3 pins are all shorted to one another.
Q604 has D and G shorted with it in circuit, I have not taken it out yet. I will update on this.

For the following I have no idea how to measure:
IC521 IC771 IC464 IC465 IC691 IC724 IC725 IC773 IC564

R613 and R869 measure at 42Kohms,
Zener diode at D608 measure good .706 and OL

Now to the Opto, I think that PC601 might be bad but I don't know how to test it. PC461 you mentioned how to test it, but I have no idea what pin is pin 5 and which pin is pin 6 and 7 and so on. How do I know which pin is which? I have tried 4 different scenarios with pin 1 being on each end, and none of the times could I get the same numbers as you did, so I think mine might be bad not sure.

I know I am throwing a lot at a time, and also requesting a lot of information, but I have browsed through this post several times, and got as much info as I could without losing my mind.
Thanks in a advance for the help.

-Nick

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

tw2005, Thank you for the replies.

I will be ordering the parts listed above for now along with those SMDiodes to start with once I have removed them from circuit and made sure they are indeed bad.

As for the other information, I am not 100% sure what all the other components you mentioned are. You said I would be better off replacing the Fet drivers, schmitt inverters, and voltage regulators. Could you give me their location code on the board so I know where to look for those. I am not sure what they are supposed to look like.
What is optos? is that a component?
What are Pfets? Locations?
The zener diodes, well I honestly checked every component with the letter D in front of its numerical location, so I think I checked those unless they have a different prefix.
The octal buffers? never heard of that before, what is than and how do I check it?

Thanks for everything.

I think you better have a good read of this thread then because if you don't pick up on those parts which are identified and I've given part numbers you have no chance with the list you have now.

2 posts above your first I even have a list of some bits you don't have .

This is in an earlier post as a guide. If you miss the schmitt inverters, any bad voltage reg and smd transistors it will just blow

I'd jot down every part mentioned throughout this thread and any others, I'd also look at Glitchers threads to his work on the same board and also Hombre, search his thread, collate all the info and you'll have a more complete picture. I'd also search on Ebay and see what are the the really large kits, sometimes they give locations of the bits. Optos - opto couplers

Q661 RJP6065, shorted_..I've used a RJP63F3A which is the newer version .
replaced Q818 2SK3018, used 2N7002
Q702 2PD601 was short, IC773 TC7SH14F was shorted Vcc-gnd(41ohms),
Replaced Q701 MMBTA92

Replaced all 78L05 regs( they appeared ok) IC724,725,771
Replaced all TC7SH14F _ IC773 bad , others looked ok, IC464,465,564
Replaced TC7SH00FU - IC691 NAND
Replaced IC521 M81707FP, used M81737FP which is same pinout higher current output
Replaced Q551 ( looked ok)

Replaced Q660,601, RJK6026 ... I had none and used STP10NK60ZFP 600V 10A N FET.

Replaced D618,652 .. RF101L4S 400V 1A super fast rectifer.

[Nick's Tvs]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

tw2005, Thank you for the replies.

I will be ordering the parts listed above for now along with those SMDiodes to start with once I have removed them from circuit and made sure they are indeed bad.

As for the other information, I am not 100% sure what all the other components you mentioned are. You said I would be better off replacing the Fet drivers, schmitt inverters, and voltage regulators. Could you give me their location code on the board so I know where to look for those. I am not sure what they are supposed to look like.
What is optos? is that a component?
What are Pfets? Locations?
The zener diodes, well I honestly checked every component with the letter D in front of its numerical location, so I think I checked those unless they have a different prefix.
The octal buffers? never heard of that before, what is than and how do I check it?

Thanks for everything.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

[QUOTE=Nick's Tvs;560507]

I have Q401 on diode setting registering 0v between the emitter and collector, and .037v between the gate and the emitter and since the emitter is shorted to the collector, I get the same result on the collector. Measuring with both cathode and anode on gate, I am getting .037 both ways. On ohms I am getting 59.1 ohms between gate and emitter/collector.
Q402 right next to it is the same thing except I am getting .044v on diode setting between collector/emitter and the gate, and with ohms I am getting 70.8ohms.
Q403 emitter and collector shorted as well, but is giving me with anode on gate .568v on diode setting, and with cathode on gate, .993v.
In ohms I get about 47Kohms.
So I am not 100 percent sure what the deal is with those, but I am assuming Q403 is good but Q401 and Q402 need replacement.


Traditionally these are in parallel so you'l just have to pull them out to see.

I tried testing the IC's but then I realized I had no clue how to and decided to do that tomorrow once i have a chance to look over all of your back and forth replies once more to see how you tested them and what results you got so I can compare from there.

If in doubt, replace. you'd be better off replacing the fet drivers, schmitt inverters, and voltage regulators etc than not. looks like optos and get blown on this board too


Driver IC M81707FP IC521 IC501 no clue how to test, but every repair kit has them and it seems like it went bad for you guys as well.
30G123 Q421 Q422 Q423
45G127 Q441
RFUS20-TM6S D401 D402
2pg011 Q401 Q402 Q403 these I am not 100 percent if all bad or if q403 is good
RF2001-TM3SW D621 D622 D641
RJK6026 Q601
RJP3034 Q621 Q622
RJP6065 Q661

don't forget about the pfet and the zener plus the opto that drives it. The 100ohm resistors for the signals to fet driver ic521, the octal buffers that send the signals through those located near sc20

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

D618 , seems typical and the tracks are probably fused too
D865 , I've seen this one mentioned in kits so i expect it will be bad
D621 , D622 if they're shorted I'd be rechecking Q621,622

reading the rest of the post, this is a big job, and this is the easy one!?

there's still a lot of stuff you have not mentioned that will be bad. hombre has a post on 1 he battled with

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

D503
D522
D524
D711

I can get similar reading for forward but reverse i either get OL or it starts charging then OL

normally these fail short

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

I took out

Transistors labeled 30G123 at locations Q421 Q422 Q423 all tested short

Transistor labeled RJP6065 at location Q661 and it tested short.
After taking it out, my SMDiode D673 and D674 labeled K696 are now working properly.

I have not taken any other transistors or diodes out. However the 6 SMDiodes that I am still registering as bad are the following:

D503
D522
D524
D711
D618 is physically burnt
D865 is located in front of, and is also shorted with D621 and D622 so it more than likely is ok, I just have to take D621 and D622 out of circuit to make sure. However the other 4 diodes were all located near the Q421 Q422 and Q423 that I already took out, and they are still acting weird.

Here are the following readings I get with the SMDiodes in circuit with my DMM on diode setting.

D503 Black on cathode red on anode .348v red on cathode, black on anode .353v
D522 Black on cathode red on anode .473v red on cathode, black on anode .726v
D524 Black on cathode red on anode .473v red on cathode, black on anode .726v
D711 Black on cathode red on anode .459v red on cathode, black on anode .641v

Back to non surface mounted diodes, I have D401 and D402 registering shorts,

I have Q401 on diode setting registering 0v between the emitter and collector, and .037v between the gate and the emitter and since the emitter is shorted to the collector, I get the same result on the collector. Measuring with both cathode and anode on gate, I am getting .037 both ways. On ohms I am getting 59.1 ohms between gate and emitter/collector.
Q402 right next to it is the same thing except I am getting .044v on diode setting between collector/emitter and the gate, and with ohms I am getting 70.8ohms.
Q403 emitter and collector shorted as well, but is giving me with anode on gate .568v on diode setting, and with cathode on gate, .993v.
In ohms I get about 47Kohms.
So I am not 100 percent sure what the deal is with those, but I am assuming Q403 is good but Q401 and Q402 need replacement.

D641 is showing on diode mode .338v going both ways.
Q601 shorted
Q441 shorted

So far this is what I found. I tried looking at some of the resistors near the transistors that went out, all tested good, I tried testing the IC's but then I realized I had no clue how to and decided to do that tomorrow once i have a chance to look over all of your back and forth replies once more to see how you tested them and what results you got so I can compare from there.

That's where I am right now, but I am going to take it slow and for sure will not plug this thing back in until I have a chance to test every single component on it haha.
However, I was able to find a few of the fets/diodes, and unless I want to pay $10 per component, I need to order from china, so I was hoping to start ordering some of those parts ASAP so I don't have to wait to long.
Also I have 2 of these exact same TV's with similar problems. This is the board that I have found has less problems, the other seems to have way more components that have gone bad, so I wanted to start on the easier one first.

Lastly here are all the locations and part numbers that I have found to be bad or think they are bad.

Driver IC M81707FP IC521 IC501 no clue how to test, but every repair kit has them and it seems like it went bad for you guys as well.
30G123 Q421 Q422 Q423
45G127 Q441
RFUS20-TM6S D401 D402
2pg011 Q401 Q402 Q403 these I am not 100 percent if all bad or if q403 is good
RF2001-TM3SW D621 D622 D641
RJK6026 Q601
RJP3034 Q621 Q622
RJP6065 Q661

Let me know what you think.
Thanks for taking the time to even read all of this, I know it's very confusing the way I presented it, I barely understand it when it's all separated out, but I have no idea how to properly organize it and what is connected together.

Thanks again

Ok, straight up, that's a lot to digest and the 30G123 being shorted straight away that's more damage than i've been exposed too so would explain the additonal diodes bad gong by what's in the kits. It may be worthwhile analysing all the kits available as that can give some clues what's needed. Sounding like a large repair in terms of number of items needed.

may be worth looking at a repair service as it's a big task to take on but you don't learn if you don't try.