Anit-Scan Feature

This feature will not  allow the vehicle to start or crank if a non-programmed  key is tried. The security light will flash rapidly as long as the unprogrammed key is left in the ON position (during anti-scan mode) until 60-65 seconds has passed, it will briefly turn OFF, then the security light will begin flashing out a trouble code (15). One of the following two steps must be followed to cancel the anti-scan  mode. Otherwise, the vehicle will remain in the anti-scan mode indefinitely.

1. Remove the unprogrammed key after you enter the anti-scan mode (before 60-65 seconds have elapsed), and then insert a programmed  key into the ignition. Turn it to the ON position, wait 60-65 seconds (until security light quits flashing) and then you can then turn the key OFF, then back ON and start the vehicle normally. Now the all previously programmed keys will again work normally.
2. With the unprogrammed key in the ignition and in the ON position and the security light flashing rapidly, wait 20 seconds, turn the unprogrammed key OFF and remove it. Now insert a programmed  key in the ignition, turn it to ON, and start the vehicle. Now all previously programmed keys will start the vehicle.