It doesn't take a "minor bump" for Sentry to begin alerting, it watches with the cameras for motion nearby. My M3 in Sentry Mode ignores bumps and loud noises that should trigger the alarm -- way too hard to trigger. What exactly is "major bump", and how does it detect glass break since over 110db of screaming third party window alarm inside the car is ignored? That's nuts. That's how thieves can break that rear window without tripping the alarm. NFG. And THAT's why I added a third party window alarm. BUT the car ignores the painfully loud screeching. NFG. Is it only sensitive to impact? Anyone here who really knows how it's programmed or wired ?