At 0650 hours, Truck Company 17 was alerted for the commercial automatic fire alarm at the Sear’s in the Chambersburg Mall.  Franklin quickly advised the alarm company was wishing to cancel, only to dispatch the AFA again a minute later.  Approximately a minute after units were on the street for the second dispatch, Franklin adivsed they were upgrading the Box to the full assignment.  This sent Engine 17-1 along with the Truck.  Crews arrived to find activated smoke detectors in the structure, but investigated and determined good intent.  Units cleared at 0734 hours.