To Program a Button As A Feature Key (example Caller ID or Day/Night )
Press the button you want to program for about 2 seconds (it will start talking to you, let go of the button)
Hit the ESI-DEX button twice
Use the Scroll Key which is immediately to the left of the ESI-DEX button – Scroll through until you see the option you want to program the button as, stop there.
Then Press the same button you are trying to program again
Then hit the # key