U.S. Spec Sportages stopped using secure audio systems after about 1997 or so.
But I may be able to get you some help. Go to
Http://www.4x4wire.com. Click on "trailtalk bbs" and follow the links to the Kia Forums. Post this question and "GaryinOZ", who has an Aussie spec 2002, may be able to talk you thru getting the system back up.