Circuit/System Description
WARNING: This page is about a different car, the 2008 Chevrolet Malibu Classic. However, it is still accessible from the selected car via links, so may be relevant.
The vehicle communication integration module (VCIM) contains two modems, one to process global positioning system (GPS) data, and the other for cellular information. Satellites orbiting earth are constantly transmitting signals of their current location, from which the OnStar® system is able to pinpoint its own location. The navigation antenna housed in the quad band radio antenna receives these GPS signals and provides the data to the VCIM to be processed. The navigation antenna is connected to the vehicle communication interface module (VCIM) via a shielded coaxial cable. The antenna cable also provides a path for DC current for powering the antenna.