Please check if this solution works for your TV.
Follow the steps to program your remote to TV. (mute+Select, Enter Code, Press Enter)
Now you could check the volume and Power button to control the TV.
To change the TV inputs, use the (ENTER) Key at the bottom right, below the '9' Key.
You could also find the word (INPUT) at the bottom of that key.
Use the (Long Press ) of the INPUT/ENTER Key.
Long Press::Keep on Pressing at that key for about 7 seconds and then the TV menu to change inputs pops up on the screen.!!
Pressing the key once will show the program guide at the bottom of screen for the channel that is on.
Not sure if this should work for all TVs. My TV Is Panasonic Viera.