Hello all and thanks in advance for all of the help. My Panasonic tc-p50x3 was hit by lightning I am pretty sure. There is no click when plugged in or when pressing the power button. There is no standby light anywhere that I see. I have taken the back cover off and I am getting 120 into the power board (mpf6908) and across both fuses. I am not getting any power at p2 or p11. I am getting 5v from pin 6 on the p6 connector going from the power supply to the A board (tnph0911). Nothing else on that pin shows any voltage. I tried to follow the thread at https://www.badcaps.net/forum/showthread.php?t=32318, but I didn't see a final solution. Any ideas or help would be greatly appreciated. Should I assume the power supply is bad or is it the A board? Is there any way to fix the boards or is the best solution to order another board? Thanks again!
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Re: Tc-p50x3 no sign of life
I would be thinking A board at this stage with 5vstb present and no relay clicks, no front LED indication. Both are controlled by the A board -
Re: Tc-p50x3 no sign of life
Thanks for the reply! Is there anyway to test this to be sure? Thanks!Comment
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Re: Tc-p50x3 no sign of life
You have 5v stdby at P6, pin6, that feeds IC5000. From that it generates 3.3v stdby, 1.2V stdby for IC8000. 3.3stdby also sent to K board where the front LED is, that's not lit.
The 3.3v and 1.2V runs the processor IC8000 which sends a signal back to the PSU to iC701 which is the PSU MCU and it turns the relays on. You have no clicks, the relays and IC701 would create F15V or 15v Stdby.
This is from a ST30 guide, but should be similar operation.
When the TV is plugged in:
AC is applied to the standby circuit in the power supply to produce STB5V.
The STB5V is provided to the A board via connectors P6 (pin6).
The STB5V from pin6 of connector P6 is applied to the Analog ASIC (IC5000) to power the Main CPU/PEAKS LDA3 (IC8000) on the A board. The Analog ASIC (IC5000) converts the STB5V to STB3.3V and STB1.2V. These 2 voltages energize and prepare the microprocessor (CPU) for program execution.
The STB3.3V from the Analog ASIC (IC5000), besides being applied to the CPU, is also applied to the remote control receiver and the power LED on the K board through connector A1/K1 (pin 3).
When the CPU receives 3.3V and 1.2V, it outputs a command that is provided to the P board. This command triggers the AC relays on the P board and only lasts approximately 15 seconds. The command applied to the P board is called different names, “F-STB-ON,TV-SUB-ON, or TUNER-SUB-ON”. The function of this command is to turn on the circuit that generates the “F15V” in the P board.
The F15V from the P board is applied to the A board through connector A6 (pins 10 and 11). This voltage is applied to several voltage regulators to generates the SUB voltages used by the A board.Comment
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Re: Tc-p50x3 no sign of life
I have to duck out but you could try a search for TC-P50X3 service manual. If you have no joy I'll try and upload or find links when I get back, or someone else may dive in and get it for you.
Checking for 5v at IC5000 going in and the others out would be a start but you'll need a manual for the pinouts and a multimeter to measure dc volts.Comment
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Re: Tc-p50x3 no sign of life
This was on another forum. However, 1. I am new to this and pretty techno dumb 2. I haven't had a chance to really read up on it. Is this what I would need to be looking at though? Thanks again!!!Comment
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Re: Tc-p50x3 no sign of life
yeah, but the resolution is so bad we're not going to see the schematic well enough , very frustrating.
Need to locate IC5000 on the A board, could be topside or underneath. If underneath, probably gonna be hard to probe with a loose board.
Search IC5000 in the pdf , at least you'll get a good block diagram to see where the 5v goes in and the 3.3 , 1.2 come out , but no pinouts there.Comment
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Re: Tc-p50x3 no sign of life
Pin 30 is 5Vstdby in, 29 is 3.3v out, 28 is 1.2v out. careful not to short out adjacent pins, blk probe on and earth point like where the screws mount the PCB and red tip on the IC pin you want to measure.
Could be tight , I've never had to check an A board this way, but I reckon if 5v is reaching that chip and no 3.3/1.2 out I think that would confirm A board.
If the 5v was missing then possibly trace back through the cct , not sure if any surface fuse is present on that line or not, have not looked and I 'm about to hit the sack as very late/early here and I work(try to LOL)
Yeah , a bit tricky for a beginner I guess. Just be aware of where the AC goes in and the PSU, don't get casual touching heatsinks etc and zap yourself.Comment
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Re: Tc-p50x3 no sign of life
IC5000 from a GT30A manualAttached FilesComment
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Re: Tc-p50x3 no sign of life
Ok. Thank you! I will try this this evening, I am sure I will have more questions. Thanks again!Comment
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Re: Tc-p50x3 no sign of life
Hey TW. I checked the ic5000 chip. I have 4.9 v on pin # 30. I have .2 v coming out of pin #29. And nothing out of pin # 28. Does this confirm it's the A board? If so, is there a way to track down the culprit of the problem within the board or is the only fix replacing the entire board? Also, does this mean the power board is ok, or is there no way to tell for sure? I want to thank you one more time for being patient and walking a dummy through this! Thanks.Comment
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Re: Tc-p50x3 no sign of life
Look, I don't know exactly a quick and easy procedure for the PSU as the A switches it on from that IC.
2011 guide for ST30 series and the startup sequence will be similar on X3 has a sequence for dead, no power, no LED.
You've confirmed no relay click at plug in.
You've confirmed 5v stdby is present at A6 pin 6
next step is to disconnect A1 connector which is the lead that feeds the 3.3v we've discussed to the K board which has the front LED and remote receiver.
Then, plug in TV and see if relays click, if NO, then it says replace A-board.
We've even gone to the extreme of confirming 5v is getting to IC5000 and NO output of 3.3 and 1.2 , the same 3.3 that goes to the K board.
Lightning seems to take out the A-boards more than the PSUs. The antenna system can often provide a path for a spike as to HDMI ports from set top boxes.
I've lost a port on mine from a very close strike, lucky me TV still works minus 1 port.
The last step is eliminating the possibility the K-board is short and dragging the 3.3v down and stooping the A board firing up.
I would consider the K as bad as feasible but unlikely, so try that step and confirm.
You may have secondary faults but at this stage your A board is dead.
you could disconnect the SC and SS board power leads just in case and see if anything changes but you said it was working and had lightning, now dead so it would be a coincidence the SC or SS died at the same time.
I can't help you much more than this.
If you replace the A board and still have a fault but the LED is lit then , just bad luck and you then need to fault find from there.Comment
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Re: Tc-p50x3 no sign of life
Ok I will try and confirm this. My next problem is. I located the model number of the A board and did a search for it. Numerous boards came up that I can order that look just like mine. However, according to one of the sites I have to determine the suffix from a suffix grid on the board in order to get the right part. Is this true? If so, I believe the suffix is "ac". (Tnph0911ac). I attached a picture if you can confirm this.
When I do a search for this, nothing comes up. Do you know where I can find this correct part at? If possible I would like to order it from somewhere that has some type of return policy. Again thanks for all your help!Attached FilesComment
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Re: Tc-p50x3 no sign of life
The image shows that you have an "AC" boardComment
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Re: Tc-p50x3 no sign of life
Hi
Just picked up the same TV with the same problem from my sister that had lighting strike happened about 2 1/2 years ago. Everything that you wrote has exactly happened while I was trouble shooting. She kept the TV in the garage and I finally picked it up after fixing my TV a week ago from reading this site. I was wondering if you ever replaced the board and where you able to fix your problem? Also, would you still remember where you purchased board. Thank youComment
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Re: Tc-p50x3 no sign of life
I have no 5V out of the power supply, is there perhaps someone here that has experience with that and knows right where to go? Funny right. I guess the next thing would be to see if i am getting power to the bridge rectifier?39 Soldering Iron burns And Counting
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Re: Tc-p50x3 no sign of life
Only getting 1.3 AC Volts to the bridge rectifier the two center taps should be AC IN. two outters are DC OUT correct?39 Soldering Iron burns And CountingComment
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Re: Tc-p50x3 no sign of life
I have a similar problem. i picked up the TV from the dump so I have 0 into it. I brought it home and first checked for bad capacitors. All checked out well and I plugged it in. I heard the relay click and the standby red led comes on steady. The screen didn't turn on or even prime. If I hold down the power button it clicks once again and when I let go it clicks 3 times. Any help would be awesome. Thanks.Comment
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Re: Tc-p50x3 no sign of life
hi there
i have the same problem with no 5v at a6 pin 6
any advice?
thanksComment
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Re: Tc-p50x3 no sign of life
You can check each pin on your main a/c plug in or at pins at your line cord to each pin on a/c pins on bridge rectifier for continuity. Should have continuity through each to rectifierOriginally posted by LITEZONER View PostI assume no responsibility for any stupid suggestions I might post.Comment
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