In order for a theft deterrent vehicle to run, a password is communicated between the Body Control Module (BCM) and the PCM. If a PCM is replaced, the new PCM needs to learn the correct password of the vehicle. When the new PCM is installed, the EEPROM calibration is flashed into the new PCM and the vehicle will learn the new password upon initial ignition 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.