Hey Len,

I don't know much about the alarm systems, but I transport and I just
drove a 2000 about 800 miles for a client.  My God!  He had an after
market alarm installed and somehow they tied that into the factory
alarm.  If you shut the door to hard, The alarm would trigger, doors
would lock and alarm wouldn't reset.  Not to mention the ignition key
wouldn't pull from the switch unless you turned the steering wheel to
just the right position.  So every time I stopped to fuel up or eat, it
took 10 minutes to get the key out and then as soon as I closed the
door to the truck, "lights and sirens" that I couldn't reset. I just
gave up, had an extra key made and kept the truck running and locked
when i stopped, because as I said, if you leave the key inside and shut
the door, they all locked.  So I don't know about the sensors, but I
feel your pain!!
Paul
Rochester NY

If it's the factory alarm there aren't any motion sensors or anything like
that (at least not on mine).  They simply tie into the door sensors so if
you try and open the doors while the alarm is activated it will trigger.
Are you sure it's the alarm?  The panic button on the dongle can sometime
get hit accidentally (or if it's flakey or low on batteries) and cause the
explorer to start honking.