How would a university think about this...?

This year I was unable to take the AP calculus course offered at my school, so I taught myself and took the AP AB Calculus test in May and felt I did pretty good (definitely a 4 and probably a 5). My question is how would colleges think about this when they see my application. I ask because I heard from someone that certain colleges only care about your grades in the AP class and only use AP scores for college credit and not admission. If this is true, would the college even care about the self initiative that I showed when I studied by myself outside of school, or will they only use this for college credit after I am admitted?