Well mine is having the same problem now.i took off the alternator because the batteries werent getting charged and took it to autozone to have it tested. well they said that it passed and so i put it back in. well im driving like not even 10 min when the gen light comes on and the voltage drop to like 9. so i dont know wat it can be. where is that fuse you guys are talking about is it in the fuse block under the hood?