Hey guys. My girlfriend rocks a protege5. Nice little car. Anyhow, battery is less than 3 months old. She's getting the battery light when she's idle. There's a wine from the alternator. I'm assuming this is the culprit. Anyone have any advice on replacing the alternator? Is there anything else I should look into?

I'm a pretty good diy mechanic. I drive a 98 pontiac gtp, with quite a bit of work done to it. But this is the first time I've had a problem with her car.

thanks in advance.