How do I remove back on Visio d650i-b2 tv after all screws are removed?

try removing batteries from remote then unplug tv for a few seconds plug back in reinstall batteries then turn on from reset in rear lower left of tv

you can search for step by step on youtube

For anyone trying to remove the back panel, literally Yank it up from that bottom right corner. Be prepared to break it but I didn't when I did that. There is a cable attached to the back panel and a board so don't just rip it off all the way make sure to unplug the cable from the board first

It is hard to say but most likely you need a new main board for that TV especially if the sound goes out after it warms up

https://support.vizio.com/s/article/ka61a000000DWK4AAO/D650i-B2-Model-Information?language=en_US

If you don't know what you're doing, DON'T OPEN THE TV UP TO FIX IT, THERE ARE HAZARDOUS VOLTAGES ON THE POWER SUPPLY BOARD, EVEN WEEKS AFTER THE TV IS UNPLUGGED!

If you don't know how to do it yourself, find some local Electronic repair shops, get quotes, try to find reviews on the shops.

What are you doing?

The main board of the tv is faulty. Can be a hardware fault or software error. You have to replace the mother board or can consult the service center.
of you wish to get some details about television repair then check the following link

http://electro-medical.blogspot.com/

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Disassemble & reassemble procedure to many popular brand TVs and other devices are given in detail with illustrations.

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