Unlocking 2002 Dodge Grand Caravan driver's door does not disarm alarm

Unlocking 2002 Dodge Grand Caravan driver's door does not disarm alarm I have a 2002, Dodge Grand Caravan and am trying to isolate an issue. If I unlock the van, from the passenger side, all the doors unlock - the alarm is disabled, and the internal lights come on. If I unlock the car from the driver side, only the front drivers side door is unlocked, the internal lights do not come on, and about half the time, the alarm goes off when I open the door.