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: General Information


    For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people. Genuine GM parts have one of these marks: California Proposition 65 Warning Warning Most motor vehicles, including this one, as well as many of its service parts and fluids, contain and/or emit chemicals known to the State of California to cause cancer and birth..

    GMC Terrain 2018-2026 Owners Manual: Alerting the Driver


    If ACC is engaged, driver action may be required when ACC cannot apply sufficient braking because of approaching a vehicle too rapidly. When this condition occurs, six red lights will flash on the windshield. Either eight beeps will sound from the front, or both sides of the Safety Alert Seat will pulse five times. See “Collision/Detection Systems” under Vehicle Personalization. See D..

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