OnStar Schematics

WARNING: This page is about a different car, the 2010 GMC Terrain and 2010 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Power, Ground, Serial Data, Microphone, and Display (UE1)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Antennas (UE1)

Courtesy of GENERAL MOTORS CORP.