- 1). Open the vehicle's trunk. Remove the tub cover, which is where your spare tire is usually stored.
- 2). Remove the sill plate. This is the area around the tub cover. You will need to unscrew the rear cargo net holders if your car has them.
- 3). Remove the side cargo net holders. Pull the side pane toward the middle of the vehicle. It does not need to be removed all the way You will see the OnStar box; it is a small silver box with a green light.
- 4). Remove the three connectors attached to the box to disable the Onstar service.
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