OnStar® Module Reprogramming
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
Important: Follow the instruction set for the part that you are replacing. Both the Vehicle Interface Unit (VIU) and Vehicle Communication Unit (VCU) have a specific set of unique numbers that tie the module to the vehicle it resides in. These numbers, the 10 digit Station Identification and 11 digit Electronic Serial Number, are used by the National Cellular Network and OnStar to identify the specific vehicle. Because these numbers are tied to the Vehicle Identification Number of the vehicle, these parts should NOT be exchanged with those of another vehicle. Failure to perform these steps will prevent the OnStar® features from functioning and will result in a customer return for repair.