Battery light being on means that either your alternator belt is too loose, alternator is bad, or bad cable connection from the alternator to battery.
The easiest is to check the tension on the alt belt. If it is tight, make sure the cable connections (you should have a plug and a battery cable connected to it, and sometimes an external ground wire). If the connections are tight, check the connections of the battery cables. If they are tight, remove the alternator and have it tested. Most auto part stores will test it for free.
And bring the battery with you. They can charge the battery back up for free.
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Thursday, October 30th, 2008 AT 2:12 PM