"AT CHECK" light is on in my car?

NOT CHECK ENGINE BUT "AT CHECK"! I don't know what that means...at first I thought it meant like that everything was "at check" like cool. Everything on your car is cool .Then I thought of it some more and decided against that idea. If my car was fine, no funky little light would have turned on. Thanks for allowing me to scream in capitalized letters. I was just frustrated because suddenly the entire WORLD WIDE WEB decided to not know what this means and give me answers totally not having to me what I asked. So back to the question what the hale?! What is that funny little light n how to make it go awaaaay! Thanks