How to Use OnStar to Unlock a Vehicle
- 1). Call OnStar directly using a cell phone or landline at 1-888-4-ONSTAR (1-888-466-7827.)
- 2). Identify yourself and your vehicle to the OnStar advisor. The OnStar advisor will ask you security questions to verify your account information before unlocking the car.
- 3). Stay on the line with the OnStar advisor until your vehicle doors unlock.
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