i tried searching first...but i couldnt find anything on the first 5 pages, and i'm pressed for time so i gotta post this really quick just fyi. but...today i was driving, and my battery light came on. last time this happened...my alternator went bad and my car died in a not so good part of town. so...it came on today, and i made it to work and back, but i'm not gonna chance it on far drives. my question is...is there a way to test the alternator to see if it's charging properly or not? i know the guy that towed me last time did, but he had some sort of box that did it. i'd like to check it myself if i can. or would auto zone be able to? i have another alt i can swap it out with...but that has to wait till tomorrow afternoon when i'm off work. and auto zone is right next door to me so if they can check it that'd be even sweeter. any ideas would be helpful