battery or alternator???

first of all, I just installed 2 brand new Naso Xenon Light bulbs (close enough to HID system)...so it was in daytime....i turned it on to have a look at it....it looks great....but somehow I forgot to turn off the headlights....and came back in the next day, tried to start my mustang...it won't start at all.....so i went to autozone, return the old alternator....got the new one....i installed it the new one....won't start....could it be the battery???? Let me know...thanks
 
your alternator will do nothing for you unless your car is running. I cannot believe Autozone warrantied it for you? Did they test it? They should have asked you some questions to find your real problem. Sorry I am looking at this from a countermens point of view...I work for CSK. Def. a battery problem. It is dead now, take it and have it charged or replaced if need be.

-Josh

P.S.-The easiest way to burn up an alternator is to use it to charge a dead battery. NEVER do this unless you HAVE to. I have had a couple alternators come back for warrantty the same day they were purchased becasue of this problem.
 
mightypoof said:
P.S.-The easiest way to burn up an alternator is to use it to charge a dead battery. NEVER do this unless you HAVE to. I have had a couple alternators come back for warrantty the same day they were purchased becasue of this problem.

:nice: good advice, ive seen a few alt's go out this way.