Circuit/System Description
WARNING: This page is about a different car, the 2010 Chevrolet Camaro. However, it is still accessible from the selected car via links, so may be relevant.
When certain modules are programmed and configured during installation, the module learns a specific environment identifier which is unique to the vehicle. The environment identifier is used to prevent swapping modules between vehicles. The body control module (BCM) is the keeper of the environment identifier. Various control modules each learn the environment identifier during their configuration process. During vehicle operation, each of these modules compare their environment identifier to that of the BCM. If the identifiers match, vehicle starting is allowed. If an environment identifier does not match, vehicle starting is disabled.