Mine work. I know because I went into CVS one day and left my son sitting in the car. I locked it, and then a few minutes later in the store I heard some horn blowing. I waited and waited for the person to disable their car alarm when I finally figured it out.... And the frantic missed calls on my cell phone from my son...
When the top is down the motion sensors are disabled when you lock the car, unless you have "the red clip" installed:
Pelican Parts - Product Information: 986-504-986-00-OEM
Steve