In order for a theft deterrent vehicle to operate, a password must be communicated between the Body Control Module (BCM) and the PCM. If the PCM is replaced, the new PCM must learn the correct vehicle password. This occurs when the EEPROM calibration is flashed into the new PCM, and the ignition is turned ON. If the BCM is replaced, the PCM needs to learn the new password from the BCM. The password learn procedure is as follows:

1. Attempt to start vehicle, then leave the ignition ON. The THEFT SYSTEM telltale will flash for 4 seconds, then remain ON for 10 minutes. Theft System Learn Mode will display Disabled on the scan tool.
2. When the THEFT SYSTEM telltale turns OFF, turn the ignition OFF.
3. Repeat steps 1 and 2 two more times. When the THEFT SYSTEM telltale turns OFF on the third ignition cycle, and Theft System Learn Mode will display Enabled on the scan tool, Attempt to start the vehicle. Once the vehicle is running, the password is learned.