Control module, OnStar, VCIM (Vehicle Communication Interface Module)

The main unit in the OnStar system is the VCIM (Vehicle Communication Interface Module). The VCIM incorporates a mobile telephone and a GPS receiver. The unit is connected to the OIM, radio, microphone, control button unit, GPS/mobile telephone antenna and data link connector via the car's wiring harness. The VCIM is fitted with one 12 pin and one 16 pin connector.