Using the “Dial” or “Call” Command
1. Press and hold 
for two seconds.
2. Say “Dial” or “Call.” 3. Say the entire number without pausing, or say the name tag.
Once connected, the person called will be heard through the audio speakers.
See also:
Battery Load Management
The vehicle has Electric Power Management (EPM) that estimates the battery's
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and extended life of the battery. ...
Safety
GM is aggressive in promoting the benefits of OnStar 8.0. New-truck buyers
get a one-year subscription to the Safe and Sound Plan, after which owners can
subscribe annually. If an airbag deploys, ...
If No Steam is Coming from the Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the ENGINE OVERHEATED IDLE ENGINE message, along with a low coolant condition, can indicate a serious problem.
If there is an engine overheat warning, but no stea ...