I have tried to replace the ignition lock cylinder, but the car has an anti-theft system in it. So the key is coded i guess. so the new lock cylnder wont work until i know i dont have to disconnect the battery anymore. I have to turn the motor off by disconnecting the spark plugs. but the car is still thinking its in the on position so the radio and dash lights stay on unless i disconnect the battery. Could it be the ignition switch?