GMC Terrain: Connected Services / Diagnostics

By monitoring and reporting on the vehicle's key systems, OnStar Advanced Diagnostics, if equipped, provides a way to keep up on maintenance. Capabilities vary by model. See www.onstar.com for details and system limitations. Features are subject to change. For updates on feature capabilities, see my.gmc.com. Message and data rates may apply.

    Connections

    The following services help with staying connected. For coverage maps, see www.onstar.com (U.S.) or www.onstar.ca (Canada). Ensuring Security Change the default passwords for the Wi-Fi hotspot and myGMC mobile application...

    Other information:

    GMC Terrain 2018-2026 Owners Manual: Emissions Inspection and Maintenance Programs


    If the vehicle requires an Emissions Inspection/Maintenance test, the test equipment will likely connect to the vehicle's Data Link Connector (DLC). The DLC is under the instrument panel to the left of the steering wheel. Connecting devices that are not used to perform an Emissions Inspection/Maintenance test or to service the vehicle may affect vehicle operation...

    GMC Terrain 2018-2026 Owners Manual: ACC Automatically Disengages


    ACC may automatically disengage and the driver will need to manually apply the brakes to slow the vehicle if: The front camera is blocked or visibility is reduced. The Traction Control System (TCS) or StabiliTrak/ESC system has activated or been disabled...

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