Red, my alarm started going off in the middle of the night too. The car alarm thinks the door opens. I couldn't stand it and didn't have a warranty to take to the dealer so I took the door apart to find out what was happening and fixed it. It been 2 years and I haven't had a problem since.
I made the original post to use the electric cleaner in May 2013. I wouldn't bother spraying the key hole, its hardly connected by sensor. Its a mess to take the mechanism apart to spray the sensor, but like I said, I haven't had a problem again in 2 years. I quick alternative is to spray through a particular screw hole noted in my earlier post, but I don't know for sure if that works, it seemed like it would if you got a straw to go deep into the mechanism, using electric spray cleaner not a greasy lubricant.