I have a battery that drains off when parked for a few days. This is a 2003 C5. The battery is 6 months old and I have had it tested by two different shops that varify it is good. In addition, I've had the alternater tested and it is good. When checking for a drian on the battery, I removed the ground and placed a test light between the negative terminal and the cable. The light was bright. While removing fuses one at a time I soon found that fuse #25 from the fuse panel under the pasenger floor board (labled BCM) when removed the test light went out. That is as far as my old school hot rod smarts took me. any suggestions on what to do to get fix the drain issue?