[Dees 911]

I just found out that my immobilizer and alarm works. I found this out when it woke me, and the entire neighborhood, at 3a.m. last night. All I know about it is there's a spot for a key on the drivers door, but I don't have a key for it and wasn't aware it even worked. I've had the car for a year and didn't have a problem with this before. I had to disconnect the battery to get it to stop. I reconnected it today and everything seems alright. Anybody out there able to give me a little insight?