I got this working in 5 Min
I used an app on my Android device called "Wake on LAN" its a blue icon and with a circle and a Ethernet cable on it, but any other app should work that can send a magic packet.
Steps followed
Switched on my LG 49UH603V-TD TV with remote
Navigated to Network Settings
Navigated to Advanced network settings
Here it should publish your TV IP Address, Subnet mask, MAC Address, and DNS Server address
Write down the IP Address + MAC address
Download and install your wake on LAN app
Add a new device to your Wake on LAN App - see my example below
Save it
Switch off your TV with the remote
Open the Wake on LAN App on your phone and hit the "Wake"
You should now be geared to switch the TV on from anywhere on your WI-FI network. This is especially helpful on the weekend when the kids are tearing the house down while you want to sleep in.
Cheers, Hope this helps
C