battery light comes on what is wrong ?
If it is in fact the battery light on the dash, your issue is with the alternator not charging properly. Probe your battery with the car off, you should have around 12.3 volts. Turn the car on, you should be seeing around 14V, since your light is on, I would think it would be close to 12V. Time for a new alternator then.
Put in a new battery and alternator
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