Alarming Noise

I just bought a 2002 Limited Ford Explorer, and the first day while driving it, the ringing noise you hear if you left a car door open, or didn't fasten your seatbelt, started going off at random times. The doors are shut, and their isn't anything on the dashboard or message center of the car, stating something is wrong...it seems like something may be loose or causing the car to sound off its "ding" whenever it wants while driving. Sometimes over bumps, sometimes smooth pavement. The reseller service shop looked at it today but claim nothing is wrong. Any suggesions?

I don't know if it's the same for the 2002 model but on my 97 explorer the GEM module controls such alarms. You may want to inquire if it's the same for the 2002's.