When you get this message on your TV while you try connecting the HDMI cable to your Asus laptop "no signal check connected devices power cable connection and source selection" then do this
Turn on the LG TV which is connected to the Asus laptop.
The TV should be set in a way that they receive signals from the input.
Then turn off the laptop as well as the TV and unplug them from the power. Do this turning off at the same time.
Now, plug in the laptop as well as the TV into the power socket and then turn on the power.
Now, you would definitely start receiving signal.y