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Shahid, Technician
Category: TV
Satisfied Customers: 11477
Experience:  I have been repairing electronic gear since 1993 as a qualified Sony tech
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I recently diagnosed an HDMI connection problem with one of

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I recently diagnosed an HDMI connection problem with one of the technicians. I have a Panasonic Viera (TC-P50UT50) that has one HDMI port that failed and the other had frequent intermittent drop outs and eventually failed. The fix was to change the A-board, which I did. I received the new A-card for the Panasonic TV, installed it, hooked everything back up, and have the same issue. Neither of the HDMI inputs will receive a signal, on-screen shows "no input". I have tried multiple sources, known good cables, and even hooked up an old DVD player using component connections and got a signal through the component interface. I also hooked an ethernet cable up to the TV and downloaded the latest software. I can display the Smart TV apps and run all of these. Any ideas, perhaps an internal cable that connects to the A-board?

Hi, my name is ***** ***** I will do my best to help you today. To make sure I don’t miss anything, please give me a minute to review your question.

- Are you able to select HDMI inputs on input source list that appears when hit Input button on TV remote?

Customer: replied 3 months ago.
I can see all input selections and I can select the HDMI inputs, 1 & 2. When I select the HDMI inputs there is only a "no signal" error message.

OK, have you tried to label the HDMI inputs (label inputs) by going into Setup menu of TV, this will enable the HDMI inputs.

Please reply back with the result.

Customer: replied 3 months ago.
I have previously done this as well. Though never had before and it worked fine. The HDMI signal had intermittent problems that looked like a failing connection that eventually completely failed. This was through the DIRECTV STB.

OK, have you tried any other video source such as DVD/Bluray in HDMI input of TV?

Customer: replied 3 months ago.
an Apple TV and BluRay player.

OK, it seems your new A board is defective, please return it to supplier and ask for replacement A board. There is no other settings in TV to enable/ disable HDMI inputs function

I hope these info will help. If you have any additional questions, feel free to ask


Customer: replied 3 months ago.
Isn't there another possible failure point? The original A board had an escalating problem with the HDMI port that I had been using for the last few years. Recently I saw drop outs that occurred at increasing frequency and eventually the port was not working, ended up with a "no input" failure. It was if there was a deteriorating condition that finally resulted in a failure. I then ordered a new A board, installed it, and see the same problem, though at this point the HDMI ports don't function but component does. So it seems that something else is causing a failure, could it be an internal cable or something else in the system?

I wish there was any other reason/ cause of trouble. HDMI ports are mounted on same A board, HDMI processor chip is also located on same A board. Only chance is to label the HDMI inputs by going into setup menu of TV that will enable them, since it didn't work then it is definitely hardware related issue/ A board internal failure.

I hope this new A board would have came with some warranty from supplier so return it and ask for another A board. I agree Panasonic plasma TVs A board has common problem with HDMI inputs failure and A board replacement is only option to get it fixed.

I hope these info will help. If you have any additional questions, feel free to ask


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