2003 Aurora, left key on and battery went dead. Recharged battery. Won't start. Turn key to on, security light out and check engine light on. Move key to start and nothing, back to on, one minute and 10 seconds later, security light back on with warning tone and (theft system fault) in the DIW. leave key on for over 15 minutes and security light remains on. Tried dis-connecting battery for over 24 hours and also put the positive and negtive cables togather with not connected to battery. Put system back on line and still have same problem. Tried different keys, used my key bob and unlock doors, still getting the same DIW message(theft system fault). All of this over a left key on accesser position and ran the battery dead. I have tried the 30 minute procedure. Any suggestions.
