Hi there, I have a 1999 expy Eddie Bauer 5.4l that has been to the shop to the tune of $400.00 to find a battery draw problem. They pulled fuses and did all the checks they could and couln'nt find it. There is definitely a draw because it will drain a battery in 5 days. No lights stay on, only the theft blinking light on the dash. Is there a chance the alternator is back feeding through itself? Is there a test for that? The shop checked output of the alternator and its fine. Any ideas would be greatly appreciated. Thanks.