Trigger to prompt if button set not clicked on

Hi,

I have a button set of 3 buttons and would like to trigger to prompt the user to click on the buttons after a delay of 5 seconds of inactivity.  Can anyone tell me the quickest way to do this?  I tried changing the state of the prompt if none of the buttons had a state of "visited" and also tried with "selected" but the prompt just keeps appearing regardless of the state of the buttons.

Thanks,

Pam.