Chosen Solution
I heard a small pop in the back of the tv then white smoke and a burning smell came from the tv. Update (07/30/2017)
Images, Model, and Board where smoke is coming from. Update (07/30/2017)
Plugged it in with the back off, the smoke is coming from burning on the board about 6 inches above the power supply.
@knarf1 well sounds like one or a couple of components went up in smoke. Unplug the set and do not use it until you identified the issue. Let us know exactly what model your TV is. Remove the back of your set and take a close look at the boards to see if you can identify which component(s) have gone up in smoke. Post some good images with your question so we can see what you see. Use this guide for that. Update (07/30/2017) Looks like multiple failure here.
Burned capacitor and possibly bad IC. You can either replace the complete power board or try to find a schematic to replace the individual parts. We still do not know what model your TV is. Repalcement power supply is available at places like this and many more.
For everyone’s reference, a POP with WHITE smoke is most always a capacitor. It might be a small one or an electrolytic The pictured problem is probably a bad transistor/SCR/MOSFET and it looks like a capacitor associated with it. However, the black burn marks could be coming out of that thru hole where the heat sink is attached and be a result of a bad solder joint. No telling how many components were damaged. The failure might have been created by another problem elsewhere. If you have a DVM and enough expertise to check components on the board or remove them and check them and find a definite bad part, it may be fixable. Remove the bad parts. Clean up all the black stuff - it creates resistance shorts. Replace parts and try again. Or just replace the board. If you can find service info, it is best to verify there is no problem on another board that lead to this.
