Chevrolet Sonic Owner's Manual: Conference Calling
Conference calling and three-way calling must be supported on the Bluetooth phone and enabled by the wireless service carrier to work.
To start a conference while in a current call:
1. Turn or press the Push/MENU/ TUNE knob.
2. Select Enter Number.
3. Enter the character sequence then select Call. See “Entering a Character Sequence” in Operation.
4. After the call has been placed, turn or press the Push/MENU/ TUNE knob and choose Merge Calls.
5. To add more callers to the conference call, repeat Steps 1 −4. The number of callers that can be added is limited by your wireless service carrier.