Panasonic LED caught in boot-loop

[anubisX]

Hello everyone, hope you're all doing fine in the lockdown. Well, I was doing somewhat fine until my TV ran into this problem today. Panasonic 50DT50, got around 2014-15 (can't remember :lol: ) was working flawlessly till this noon. It's connected to the computer via HDMI and I use it as my computer display. I was watching a movie and suddenly the screen scrambled and the display went black. I turned it off and on to find out that the display is all grainy like old antenna days and then vertical lines appeared and the TV started restarting on it's own. The SMART VIERA logo will appear and the TV will restart for 8-10 times and then the lines and grains and the bootloop persists, remote doesn't seem to work although the LED suggests that the TV is catching signal. I'm clueless and need help with it. Any suggestions?

 

[VRavichandar]

Hello everyone, hope you're all doing fine in the lockdown. Well, I was doing somewhat fine until my TV ran into this problem today. Panasonic 50DT50, got around 2014-15 (can't remember :lol: ) was working flawlessly till this noon. It's connected to the computer via HDMI and I use it as my computer display. I was watching a movie and suddenly the screen scrambled and the display went black. I turned it off and on to find out that the display is all grainy like old antenna days and then vertical lines appeared and the TV started restarting on it's own. The SMART VIERA logo will appear and the TV will restart for 8-10 times and then the lines and grains and the bootloop persists, remote doesn't seem to work although the LED suggests that the TV is catching signal. I'm clueless and need help with it. Any suggestions?

That is sad.
Remote control does not work - is there a light to indicate the remote is being sensed? (in my 2011 model the power indicator blinks when a remote key is pressed). If it is not sensed, it is deemed to be due to "A" board fault. Do not attempt to restore firmware at this stage.

Is your cable / dth tv HDMI connected directly to your TV? This has caused problems for a few people.

Hope you have disconnected all input cables. Make sure that there is no sd card / usb drive / any other connections to USB ports as well. Try restarting.
When the error occurs, If the indicator light is blinking, count the number of blinks and see what it corresponds to.

A must try is to disconnect the TV from the mains and leave the TV off for a day or more if you can. Try powering on after that. (This worked for me with an older model).

 

[anubisX]

Thanks for your inputs.

Remote works coz I can see the blinks when I press any key on the remote. I don't use it as TV, it's connected to the Mac Mini via HDMI. One USB port is connected to the Antec Backlight LED strip. However, I've disconnected everything and kept it unplugged overnight.

I'll try counting the blinks it make when rebooting but the TV continuously reboots so the LEDs will keep on blinking before it gets steady.

 

[VRavichandar]

Thanks for your inputs.

Remote works coz I can see the blinks when I press any key on the remote. I don't use it as TV, it's connected to the Mac Mini via HDMI. One USB port is connected to the Antec Backlight LED strip. However, I've disconnected everything and kept it unplugged overnight.

I'll try counting the blinks it make when rebooting but the TV continuously reboots so the LEDs will keep on blinking before it gets steady.

I stopped connecting any device that draws power from the TV's USB ports.

How long is the hdmi cable length between macmini and tv? Search these forums where another member has posted about hdmi ports malfunctioning in an avr - he had some lengthy cables connected and other members have suggested reducing the length. It may not directly be related, but...

Trying a different hdmi cable is also suggested. See if the problem happens if you switch to non-hdmi inputs (even if there is no connection to any devices)

 

[VRavichandar]

Hope you have unplugged the TV from the socket to allow the tv to "cool off!"
Meanwhile check your entire power supply circuit to the TV - plug points, spike buster, power cable, extension wire if any, for actual voltage, earth voltage leaks (use a simple tester on the ground pin if you do not have a meter), if any.
Should the problem persist, try connecting the TV to a different power circuit - most homes with 3 phase power supply have different circuits for different rooms etc.

 

[anubisX]

Everything is disconnected, the HDMI cable is Belkin 3ft. The TV is connected to a spike-buster where the MAC is also connected. I've tried disconnecting the TV from the spike-buster and plug in wall-socket but nothing's changed. All other devices work fine though.

As the TV is wall-mounted, the back of the TV has accumulated good amount of dust, could that be a reason of any problem with the weather being pretty damp in my area. Coz I've faced similar issue with my computers as well in the past.

 

[kbhuvi]

Everything is disconnected, the HDMI cable is Belkin 3ft. The TV is connected to a spike-buster where the MAC is also connected. I've tried disconnecting the TV from the spike-buster and plug in wall-socket but nothing's changed. All other devices work fine though.

Hi

You need to hard reset your tv. I am not familiar with your exact model but panasonic viera can be hard reset as follows.

1. Remove all connections from tv
2. Remove the power cable from switch board.
3. Hold the power button and the program + button on the tv (note - on the tv unit NOT on the remote).
4. Ask someone to plug in the power cable of the tv and switch it on.
5. Keep holding the power and program + button on the tv till it boots up and the logo is displayed.
6. Release the buttons and wait for the tv to go through the set up process

Regards

 

[anubisX]

Thanks for the inputs.

I tried what you suggested. Held on to the Power and Channel + button, plugged the TV in, powered on, the LED blinked but the screen remained black as long as I'm holding on to the buttons. Once I let go of the buttons, the raining (noise) starts.

Yesterday, it stopped rebooting. Once the TV is powered, the LED will blink 8-10 times and the noise shows up with the box appearing in the middle that shows Smart Viera logo. The color of the noise will change with different patterns.

 

[kbhuvi]

Thanks for the inputs.

I tried what you suggested. Held on to the Power and Channel + button, plugged the TV in, powered on, the LED blinked but the screen remained black as long as I'm holding on to the buttons. Once I let go of the buttons, the raining (noise) starts.

Yesterday, it stopped rebooting. Once the TV is powered, the LED will blink 8-10 times and the noise shows up with the box appearing in the middle that shows Smart Viera logo. The color of the noise will change with different patterns.

If you have a multimeter pls check if the power adapter is giving the desired voltage. If it is then you can proceed

Remove the power plug. Hold the power button on the tv for 30 seconds WITHOUT plugging in the power cable.

Wait for 5 minutes. This time hold the channel - button and power button and repeat what i said in my previous post. This time hold both the buttons till the tv led turns green. It may take upto 30 seconds.

If there is any software corruption, the software will be reinstalled. If the problem persists, then the nand flash memory is gone. New motherboard is the only solution.

Regards

 

[anubisX]

No changes seen. It seems like a hardware fault. Panasonic haven't sent anyone yet, let's see.

 

[anubisX]

Panasonic service person came, he did something from his phone (service IR remote, I guess) holding on to some buttons on TV back-panel. The picture came back and he did a reset from my remote. He said that the problem came from the motherboard and it'll likely come back again but can't say when (could be in a month or in 2 years). Told me to keep the backlight on low setting for prolonged usage.

Thanks a lot for all your inputs and help.

 

[VRavichandar]

Panasonic service person came, he did something from his phone (service IR remote, I guess) holding on to some buttons on TV back-panel. The picture came back and he did a reset from my remote. He said that the problem came from the motherboard and it'll likely come back again but can't say when (could be in a month or in 2 years). Told me to keep the backlight on low setting for prolonged usage.

Thanks a lot for all your inputs and help.

Great!