# "no signal" problem on my panasonic plasma



## readymademack

I have a 42 inch panasonic plasma TH-42PX80B, its nearly 10 months old now and its nearly out of warrenty so i need to fix this problem i'm having. 
every now and then when i turn my tv on it will say no signal on dtv, when i rescan the channels it wont find anything and switch to analog. i can keep rescanning but nothing comes up. i usually unplug everything and cut power completely and leave it for ten to fifteen minutes and try it all again, sometimes it works and my tv will find all the dvb services but sometimes it takes hours to get working again. i have tried another tv (37 inch lcd) on my coaxle when the problem happens and that will work fine so i know its not the signal. 
I have spoken to panasonic many times about this problem because it started happening 6 months after i purchased the tv and they have had engineers pick up my tv twice to try and fix it but both returned the tv after 2 weeks saying they had no problems. 
i really dont understand whats going on with it as when it works it can be fine for weeks but every now and then ( and its happening more often) i will turn the tv on to find no signal and have to mess about unplugging and hoping it comes back on. 

i'm hoping somebody might know whats happening so please all feedback is appreciated


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## DonaldG

Hi & welcome to TSF :wave:

I Presume that you have had the Aerial and coax feeder checked and found to be OK (I would think it is if you are getting a good solid analogue signal.)

It would appear that there is an intermittent fault in the TV - the hardest type of fault to track down!

However it is still under warranty therefore it is not recommended that try & fix it yourself.

Pursue the fault procedures with the place where you bought it from. Keep a detailed and clear record of all the faults.

Keep a history log of when it was returned for repair, how long it was away etc. This is the evidence of it's unreliability.

If you have enough proof of it being faulty from early days, *try* demanding a replacement TV because you have lost faith in it's reliability. 

The fact that the 'engineers' have not found a fault/problem does not mean that there isn't one.


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## readymademack

hi, thanks for the fast reply, to be honest i'm kinda tired of all the messing about now and was thinking of buying a freesat box instead of using the built in digital reciever, if the problem with my tv is the freeview side of things then this would be ok i assume?.

also to fuel my anger today i have noticed a pixel flickering, i know the tv was a low price unit but i didnt think i would have so many isues, and after such a short period.

exactly how many dead pixels do i need before panasonic will replace my tv?


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## DonaldG

I am not sure on how many dead pixels must be accepted on a TV - That is something that you will have to check.

Whatever, I wish you well with getting it all sorted out.

Regards


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## RickRedSox

Hi, I have 46in Panasonic TH-46PZ85B 11 months old with exactly same problem. I have already had it repaired once even though the service centre claimed no fault found they replaced the tuner board. It's still doing the same thing - intermittently giving "no signal" message even though I know the signal is good. Takes hours to be left alone and then works fine. I was going to give up and use a freeview box but now I know its not just mine I will go back to Pana service again. I noticed that when the "no signal" fault occurs, the signal condition monitor on the setup menu shows 50% signal strength but 0% signal quality. Does yours do the same ?


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## Maximillion

I also have a 46" panasonic plasma TH-46PZ800A. Exactly the same problem. Sometimes the DVB-T tuner card does not work. I have a digital set top box that I use through AV1 (for recording) and it always works so I know it is not the signal. I sent my TV to get repaired last week, they found no fault but claimed to have replaced the tuner card, took it home and its doing the same thing again. I'm not a techy but it seems pretty clear the the cards being used by panasonic are crappy.


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## Maximillion

I have just noticed the following:

The problem is related to the HDMI inputs. I have my PC and Xbox connected to HDMI1 and HDMI2. When I turn the TV off at the switch, diconnect these inputs and turn the TV on again, the DVB works perfectly. Turn it off again, plug in the HDMIs, turn it back on, "no signal" from DVB. I have just repeated this procedure 3 times and got the same result each time. Does anyone else have the same problem?


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## Maximillion

Ok,

Its the HDMI connection from my PC. When this is plugged in to any of the HDMI inputs the DVB function displays the "no signal" msg. I tried the following procedure. Turn TV off at TV switch, disconnect the HDMI from the PC, turn TV on, DVB works perfectly. Turn TV off, plug HDMI from PC in, turn TV on, DVB displays "no signal". The Xbox HDMI does not effect the DVB in any HDMI port. Hope this helps.


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## Done_Fishin

There must be a signal that activates the input and cuts off other internal circuitry. Similar to the old SCART cables that gives power to a pin inside the TV when an external device is switched on.

This can only be overcome if you find out what signal is doing it then use a break out box to disconnect that pin, possibly using a switch so that it can be activated manually.

Since the whole purpose of this pin is to automatically switch over to an external source when the socket is plugged in and the external device switched on, it will be deemed as working normally.

Perhaps you might want to check the menu's inside the TV to see if there is a software method of stopping an automatic switchover, allowing you to manually check the source.

Thanks for providing in-depth analysis of your problem. It may well help others who have similar problems in the future.


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## justjackie2

HI i have a panasonic plasma model number TH-42PWD6
i watch it via a set top digital box and when wanting to watch a dvd i swap the cables from set top box to dvd player and then back again when i want to watch tv.
this is normally fine until i watched a dvd last week , swapped cables back to tv and no signal.
have had an aerial man in to check signal with meter he says signal is good.
the plasma is wall mounted with cables inside the wall.
had no signal for over a week now keep un-plugging it leaving overnight and trying again but nothing.
can anybody please help ?:sad:


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