Panasonic tc-50Pu54 dinostic code...

https://www.manualslib.com/manual/835783/Panasonic-Tc-P50s2.html?page=17

https://www.google.com/search?q=Panasonic+TCP50S2+7+blink+code

and finally, what normally happens

https://www.fixya.com/support/r29790007-repairing_own_television

..

Here's the manual; http://www.manuals365.com/swf/panasonic/tc50pu54_adv.html Hope this helps.

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices.
http://electronicshelponline.blogspot.com/
If blinks continue without any pause, the main board is faulty.
Search the site by type in the "brand name" to your device, in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices.
http://electronicshelponline.blogspot.com/
If blinks continue without any pause, the main board is faulty.
Search the site by type in the "brand name" to your device, in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.

I have come across 6 blinks; 7 blink and even 10 blinks.
the video below may throw some light. Not sure if the blink codes are universal across models. Panasonic plasma tv 7 red blinks of *****

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electronicshelponline.blogspot.com/

Yes. It is probably a problem with the internal power circuitry. Look in the circuit board area where the power cord mates with it for capacitors that have bulging tops (instead of the flat tops that are normal). If you see even one, you need to replace all the large capacitors othe power supply section (normally around 5 or 6).

try this-
http://elektrotanya.com/panasonic_tc-p50st30_chassis_gpf14du.pdf/download.html

Check and replace its Z-sustain board. Visit the site named 'Electro-help' for more details. Click this link. View it in "Timeslide" or "Flipcard" option, which can be selected from the drop down box menu by the [Sidebar] tag, at the top left corner of the display window. You can also click the [Home] tab to see the latest updates. It will make search easy. There are more than 1350 posts to different brand TVs now. Pull up older posts there.