If you press the phone button on the steering wheel, then it will default to the Onstar service (I think). But if you have your phone paired and do not want to use the Onstar service, then you simply make a phone call from your cell phone and it will switch over to the Bluetooth. I'm pretty sure that's how it is.
Now if you have 2 phones paired, then you have to go into configuration and choose phone options and then choose which phone you want connected.
2017 Camaro ZL-1 A10
2013 Jeep Grand Cherokee Hemi 5.7 - Tuned!!
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