Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring System. If a diagnostics check is needed between e-mails, push 
, and an Advisor can run a check.
See also:
Reporting Safety Defects
Reporting Safety Defects to the United States Government
If you believe that your vehicle has a defect which could cause a crash or could cause injury or death, you should immediately inform the Nati ...
Transferring a Call
Audio can be transferred between the Bluetooth system and the cell phone.
The cell phone must be paired and connected with the Bluetooth system before a call can be transferred. The connection proces ...
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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