I am looking for help. I have a 99 Ford Mustang v6 5speed. We have replaced the battery 3 times in the past 8 months and the battery is now dead again after replacing it less than a month ago. We believe the previous owner had tried to wire things himself or thag there is a short. I can close the doors while the car is running and they will lock and unlock themselves. There was an amp previously but we thought by taking it out maybe it would prevent the draining. Would this be the alternator that's bad?