OnStar Description and Operation (UE1 with IOR): Bluetooth®
WARNING: This page is about a different car, the 2018 Chevrolet Trax and 2018 Buick Encore. However, it is still accessible from the selected car via links, so may be relevant.
With the OnStar TCP system Bluetooth® resides in the radio. Refer to Radio/Audio System Description and Operation for further details.