TC-P50GT25 blinks 4 or 10

[djw43]

Hello Forum,
Thanks for being a great source for DIYer's
I have not been lucky enough to find the tech manual/service manual for my exact manual, so I have been referencing a few from 2010 for G25 and another from 2011 for GT30.
In order for me to complete the diagnostics for my blinks, I have 2 questions:
1.) When i connect AC, I get a few relay clicks right away, then 15 seconds later i get another few clicks. My questions is whether I power on and view blinks after the first clicks or after the later second clicks? Because right away I get 10 blinks, and if i wait until after 2nd set of clicks, 4 blinks.
2.) In diagnostics I am checking voltage on pin 9 on P7 in one flowchart, and the tree is "is there 3V present?" when turned on, another chart asks "is pin 9 high (3V) before the TV shuts down?". My question is after I use the start/power button the TV shuts down right away, like in a second. After it has shut i do read 3.13v on that pin, but it is after the one second it takes to shut off (SOS?) Am I a "yes" branch or a "no" branch for whether i see 3v?

ultimately i am trying to determine what board or boards i need to fix or replace.

thanks,
david

[Alastair E]

Re: TC-P50GT25 blinks 4 or 10

SC Board is the most suspect on recent Panasonics. Power Off, Check for short-circuits on the V-SUS supply on the SC Board.

--The boards of these sets are rather hard to get (Because they always blow up, due to crap screws and poor cooling) and can be expensive.

There's Co's in the USA Moduslink? that repair them.....

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

Hello Forum,
Thanks for being a great source for DIYer's
I have not been lucky enough to find the tech manual/service manual for my exact manual, so I have been referencing a few from 2010 for G25 and another from 2011 for GT30.
In order for me to complete the diagnostics for my blinks, I have 2 questions:
1.) When i connect AC, I get a few relay clicks right away, then 15 seconds later i get another few clicks. My questions is whether I power on and view blinks after the first clicks or after the later second clicks? Because right away I get 10 blinks, and if i wait until after 2nd set of clicks, 4 blinks.
2.) In diagnostics I am checking voltage on pin 9 on P7 in one flowchart, and the tree is "is there 3V present?" when turned on, another chart asks "is pin 9 high (3V) before the TV shuts down?". My question is after I use the start/power button the TV shuts down right away, like in a second. After it has shut i do read 3.13v on that pin, but it is after the one second it takes to shut off (SOS?) Am I a "yes" branch or a "no" branch for whether i see 3v?

ultimately i am trying to determine what board or boards i need to fix or replace.

thanks,
david

As per Alastair, The TNPA5081AP SC board is the most likely culprit here and has shorted the P-board.

Try searching TNPA5081 or your model or any FHD of that era eg 42,50,54 G20 / 25, GT25, V20 and there should be heaps of stuff to read.

Moduslinkpts repair boards or there's kits or you could try and work it out from the SC repair thread I did.

the SD/SU boards will have to be checked for shorts as well

[djw43]

Re: TC-P50GT25 blinks 4 or 10

thanks very much for the responses !
I did have another question, because I did check Vsus and Vda and p15V for shorts first, and when i measured resistance they each started low, like a few hundred ohms, but as I keep the multi meter in place the R crept up over 2kohm, but it was weird to watch the resistance increase for 5-10 seconds. Is that normal?

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

thanks very much for the responses !
I did have another question, because I did check Vsus and Vda and p15V for shorts first, and when i measured resistance they each started low, like a few hundred ohms, but as I keep the multi meter in place the R crept up over 2kohm, but it was weird to watch the resistance increase for 5-10 seconds. Is that normal?

ccts charge, try reversing the probes. SC2 should start at around 300Kohms and up to 2-3meg. The P15V may be shorted or dragged down in this one as well on that SC board

[djw43]

Re: TC-P50GT25 blinks 4 or 10

ccts charge, try reversing the probes. SC2 should start at around 300Kohms and up to 2-3meg. The P15V may be shorted or dragged down in this one as well on that SC board

Thanks again, I switched from a digital to an analog multimeter, and even though I was getting odd readings with the probes one way, I was getting readings that made sense after switching them. The SC is a few hundred ohms and I will replace or with the spectacular guides, I may try to repair. The SS was reading approx 2k ohms, so perhaps that will be next to go, but I want to see if the TV will turn on after fixing the SC before I change the SS.
thanks

[Alastair E]

Re: TC-P50GT25 blinks 4 or 10

In some cases--a faulty SS board can kill a new/good SC board--so I would remove both boards and check ALL the IGBT's and MOSFETS on both boards for shorts, and also check both buffers too, before putting power anywhere near the set!....

[djw43]

Re: TC-P50GT25 blinks 4 or 10

In some cases--a faulty SS board can kill a new/good SC board--so I would remove both boards and check ALL the IGBT's and MOSFETS on both boards for shorts, and also check both buffers too, before putting power anywhere near the set!....

ok thanks Alastair, I will check both boards, I just need to do some research for how to test those transistors. I am happy to have a plan and a road map for some directions, which this site provides!

[keithf2]

Re: TC-P50GT25 blinks 4 or 10

i know this is not the correct place to ask this question but I can never find the correct way to start a thread. what I want to know is how do you make a connection on a LG 42PJ550 control board to get the test pattern. Thanks in advance.

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

i know this is not the correct place to ask this question but I can never find the correct way to start a thread. what I want to know is how do you make a connection on a LG 42PJ550 control board to get the test pattern. Thanks in advance.

Time to learn

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

Thanks again, I switched from a digital to an analog multimeter, and even though I was getting odd readings with the probes one way, I was getting readings that made sense after switching them. The SC is a few hundred ohms and I will replace or with the spectacular guides, I may try to repair. The SS was reading approx 2k ohms, so perhaps that will be next to go, but I want to see if the TV will turn on after fixing the SC before I change the SS.
thanks

I don't think I've read a report of bad SS in these yet. Bad SS in these won't take out the SC as they are not interconnected like the HD models .

focus on the SC and making sure the SD/SU boards are good

[djw43]

Re: TC-P50GT25 blinks 4 or 10

Hello again gentlemen,

I am in the process of checking the SC/SD on my 2010 TC-P50GT25.
Can you guys recommend a handbook, I am not sure whether to follow the 2010 G20 G25 or the 2011 GT30 handbook for checking these 2 boards connected to the SC, I started using the G25 handbook, disconnected the 4 screws and disconnected the 3 - SC41, SC46, SC42, I unplugged SU11-SD11 ribbon, and jumped SC50.
as per:
https://www.badcaps.net/forum/showpo...0&postcount=15

I see 2.5M TPSU15
220k at TPSU16
but i am getting low reading on TPSU17
and TPSU18 to (VF_GND) is in the mega ohms, not grounded (I am using the metal ring around the screw hole for VF_GND not the case in the screw hole.
But either way TPSU18 is not grounded, neither is the ring around the screw hole?(VF_GND) with the screw removed.

I am struggling some between digital and analog multimeters, I am getting different values on the analog when i switch probes, and with the digital I can get increasing or decreasing resistance depending on the probes reversing.
Meanwhile I have at least 6 Qxxx components on the SC that have a least 2 legs shorted. (tone)
thanks guys

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

just use the pin numbers at the relevant connectors on the buffer boards and gnd at the mounting plates. Try switching the probes around but so far for the Su you've listed

Vfo states 2.2Meg, you say 2.5 meg, i usually get about 1.9Meg on a fluke 73.

This would normally show short on a bad board, I say pass

VSCN-F (TPSC1) states 221K, you say 220K, I get 220K- pass

5V_F states 5.7Meg, you report ? What is the range limit for your meters? I get as quoted with my meter

confirm Su 5V_F,

Now repeat process for the SD, looks promising

gnd on these has nothing to do with chassis gnd

[djw43]

Re: TC-P50GT25 blinks 4 or 10

thanks!
I will measure again, the boards are removed, will the results be useful?
Otherwise I can replace them.
I really appreciate the help, and I am amazed at your fast responses!
thanks
dave in NJ USA

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

thanks!
I will measure again, the boards are removed, will the results be useful?
Otherwise I can replace them.
I really appreciate the help, and I am amazed at your fast responses!
thanks
dave in NJ USA

I'm bored and just sitting here but going shortly. yes they are as it will save you money and as you start looking you'll find parts are getting more expensive and hard to get but the repair services are now growing as that's the only option or self repair if you're good at this stuff.

[djw43]

Re: TC-P50GT25 blinks 4 or 10

I think i was unclear.
I am going to measure the resistances again, it is ok to measure them out of the case?
Instead of replacing them back in the case to measure.
I have seen your extensive info on TNPA5081 and my plane is to purchase a repair kit for that board and repair it myself.
thanks again have a good night

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

I think i was unclear.
I am going to measure the resistances again, it is ok to measure them out of the case?
Instead of replacing them back in the case to measure.
I have seen your extensive info on TNPA5081 and my plane is to purchase a repair kit for that board and repair it myself.
thanks again have a good night

for sure out is fine and so is insitu, if you leave them in then you won't have the drama of getting the ribbons in again straight as they can be fiddly to get right.

before you rush off and get a kit , list which ones you're looking at as some do not have everything.

look at IC771,773, q701,702,818 IC521 and see if you reckon you can handle replacing those. what soldering gear do you have?

[djw43]

Re: TC-P50GT25 blinks 4 or 10

i will look at those, i have a haiko FX-888D soldering iron, the smallest components i have removed and replaced were LEDs on a radar detector.
thank you

[tw2005]

Re: TC-P50GT25 blinks 4 or 10

i will look at those, i have a haiko FX-888D soldering iron, the smallest components i have removed and replaced were LEDs on a radar detector.
thank you

Hot air may be handy but I used 2 soldering irons, allowed me to heat 2 sides at once , the tracks tear and lift easy if not careful, usually I flood the pins with solder , can usually lay the tip on a low angle to cover more pins to get these off in one hit.

flux helps and i need a magnifier to see what I'm doing

$85 for modus repair, kits look expensive and deficient, utsource if you want to ordr the bits and wait weeks for them to arrive, there maybe other options for supply in the US but that I have no knowledge

[djw43]

Re: TC-P50GT25 blinks 4 or 10

$85 looks pretty good right now!
As i went down your list they looked more and more difficult.
IC771 with AE on it 3 pins under and one above, doable
773 is smaller and looks like it has 5 solder pins
q701 is small but accessible
702 a little harder
818 even smaller, 3 pins
IC521 chip 1737FP, i would not know how to remove that one, copper braid? hot air?

I salute your skill!

well I am going to look into modus for my TNPA5081, thanks
I will be back...