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Tim Nolan
Tim Nolan, TV Repair Technician
Category: TV
Satisfied Customers: 19454
Experience:  Factory trained TV repair technician. U.S. NAVY trained.
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TH50PZ80U - same problem as a bunch of people. 10 blinks of

Customer Question

TH50PZ80U - same problem as a bunch of people. 10 blinks of the Power LED. Heres the difference, if I unplug the TV for anywhere from 5 min to 2 hours, it works again until I turn it off. So its some type of overheating in the power supply I assume. I am thinking of replacing the A board, but since thats expensive, can someone tell me how to make sure its the A board. I would need pretty specific instructions. I am comfortable w/ electronics (electrical engineer) but not TVs. Thanks
Submitted: 6 years ago.
Category: TV
Expert:  Tim Nolan replied 6 years ago.

Thank you for posting your question on Just Answer! I will be happy to help you with this problem. Can you please give us some more information so I can better answer your questions.

 

-Do you get 10 blinks when you plug it in or 10 blinks after power button is pressed?

 

Please give me this information and I will be happy to assist you further.

 

Thank you,

Tim Nolan

Customer: replied 6 years ago.

It starts when I plug it in. If I press power and hold it in, the 10 blinks start again. Seems pretty common, sadly.

Expert:  Tim Nolan replied 6 years ago.

You dont by chance have a computer hooked to the tv through HDMI do you? OR a HD Explorer 8300 cable box?

 

 

Tim

 



Edited by Expert TV on 5/8/2010 at 7:53 PM EST
Customer: replied 6 years ago.
No, i have a motorola HD box, and since I read about the HDMi issues, i have disconnected all HDMI cables already. I left the coax in, but I assume that cant be an issue?
Expert:  Tim Nolan replied 6 years ago.

OK very good then we definitely have an internal failure in the set. The reason 10 blinks is so common on this set is because there are so many things that can cause it. There is a long troubleshooting chart that I can walk you through if you like. Do you have the tv open and a meter handy?

 

Tim

 

Customer: replied 6 years ago.

No, I can't do it right now (kids). Would you suggest sending me the steps or scheduling a time later to walk me through it? Is it fairly easy to troubleshoot?

 

Customer: replied 6 years ago.
actually, the boys are sleeping.. I am going to go open the tv now, will be 10 min
Expert:  Tim Nolan replied 6 years ago.

Ok once it is open the first thing i need to know is:

 

Do the AC relays click after TV is plugged into AC line?

 

Tim

 

Customer: replied 6 years ago.
i should be able to tell by sound i assume, and yes they do (still opening)
Expert:  Tim Nolan replied 6 years ago.

Ok check to see if we have 15v at Pin 7 of connector P6/A6 when the tv is plugged into the AC line.

 

Use any of the metal on the back of the panel for ground when checking this voltage.

 

Tim

 

Customer: replied 6 years ago.

Ok.. doesnt seem like anything to P6, connector 7.

 

Then, when i was looking for A board, i disconnected and reconnected AC, and this time I did not hear relays.

 

Then I did it again, relays clicked.

 

No voltage at pin 7 of A6 or P6.

 

Expert:  Tim Nolan replied 6 years ago.

No voltage at pin 7 is what I suspected, you have a bad P board it is not putting out the 15v line therefore the tv will not run. We have replaced 20 p boards to every A board in this model with this symptom so I am quite confident that you will fix it with the P board.

 

ETX2MM704MGH is the part number you will need.

 

 

If you would like any additional information or have more questions please don't hesitate to ask!

 

Please never accept an answer until you are 100% satisfied and feel you can leave positive feedback. If I have answered your questions and met your needs then please press the green "accept" button. Otherwise please feel free to ask anything else to get your problem resolved. Positive feedback is always appreciated!

Thank you,
Tim Nolan

Customer: replied 6 years ago.
Sounds like we are close. Last question. What leads can I test to make sure the P board is getting power, to make sure its not the power supply ? Just want to make sure before I replace the P board.
Expert:  Tim Nolan replied 6 years ago.

The P board is the power supply.....

 

The power supply is getting power because the red light is blinking on the back, you know you have AC because it is clicking so there wouldn't be anything to test, you can hear and see that it has power.

 

Let me know if you have more questions.

 

Thanks,

Tim

 

Customer: replied 6 years ago.

right, duh. been a few years since I did this stuff :-)

 

VERY last question, i promise. Scale of 1-5, 5 being hardest.. how easy is it to replace P board? I assume just the series of connectors ? Or should I have someone do it?

 

Thanks a ton, very helpful. will be happy to be a reference if you need one.

 

Marc

 

Expert:  Tim Nolan replied 6 years ago.

Marc,

 

Taking the back off is harder then replacing the board...if you look the board we are going to change is the board that P6 is on, so you will need to disconnect those three larger connectors, then above them you have a smaller connector, and then in the top right and top left of the board there is 2 large 2 wire connectors you have to take these off as well.

 

Then you have to unplug the AC input wire which is a large 2 wire connector in the bottom right. This description should be close, I am going off of memory as I don't have a board in front of me but it should only be those 7 connectors and then about 9 screws.

 

Disconnect the connectors, remove the screws, pull the board out, put the new board in, put the screws in, make sure you remember where the wires were and plug them back in and you are all set. of course...make SURE the power is DISCONNECTED before you begin ;)

 

Let me know if you have more questions, I am here to help.

 

Tim

 

Tim Nolan and other TV Specialists are ready to help you
Customer: replied 6 years ago.

Tim-

Replaced the P board. Now, the relays click, and bo flashing LED. But then, we I press Power, I get 2 blinks.

 

When I test P6 pin 1, I get voltage but then it slowly drops down to 0. Does this mean the A board is also bad in your opinion?

Customer: replied 6 years ago.

Could it be the voltage adjustment to Vsus - I just read in the service manual? I didnt do that.. I'll try tonight. If you get a chance, pls let me know any advice.

 

Expert:  Tim Nolan replied 6 years ago.

You are getting 2 blink pause 2 blink pause repeat?

 

Sorry I have been slamed with work, I will do my best to help you as fast as possible.

 

Tim

 

Customer: replied 6 years ago.

No prob. yes, its 2 blinks pause repeat, AFTER turning on. When just plugged in, I get nothing automatic. No priming, etc. Relays still click.

 

I found the diag manual and I followed the 2 blink route, and it seems to point to the D board, but I am nervous about spending more $. Maybe its time to call a repair shop?

Expert:  Tim Nolan replied 6 years ago.

OK here are some notes on the 2 blink:

 

-Reseating the connector P25 may solve the problem

-unplug the unit disconnect the connectors A5, A6 and A7 apply power to the tv. If a white screen comes up and all voltages check normal replace the P board

 

Check these two things and then let me know what happens, also you said you get voltage on P6 but it slowly drops, do you get the full 15 volts now as where we got 0 before?

 

I have to go run 5 tv service calls, I will be back once done and check in on you, sorry I cannot stay but I have customers waiting on me...Sorry.


Tim