My charging indicator is lit. A voltage check at the battery with the car running shows less than 12 volts. I've fully charge the battery and checked all the connections and fuse (#15). If the alternator would a double digit price (and easy to swap), I'd replace it as part of the troubleshooting. But, a $500+ cost plus the pain of draining the coolant makes me question whether there might be another cause. Any recommended tests that can be performed with a voltmeter? Are there other fuses or relays involved in the charging system? Other... Thanks for your help.