See also:

Service Only Mode
This power mode is available for service and diagnostics, and to verify the proper operation of the malfunction indicator lamp as may be required for emission inspection purposes. With the vehicle ...

Using the Dial Command
1. Press . ► For vehicles without a navigation system, the system responds “Ready,” followed by a tone. ► For vehicles with a navigation system, the system responds with a tone. Aft ...

Transferring Service
Push to request account transfer eligibility information. The Advisor can assist in canceling or removing account information. If OnStar receives information that vehicle ownership has chan ...