If I manually enter my aa ff number, most of the time it does NOT locate the itn, especially if I am checking in before midnight and flying after midnight. It is easier to use the locator, which always works.
[In LAS (Vegas), there are two types of kiosks (1)dedicated aa terminals (near the check-in area) and (2) universal kiosks, these allow check in for over a dozen airlines--these have no slot for swiping an aa card.]