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 2018-2025 Owners Manual: Diesel Exhaust Fluid


    Diesel Exhaust Fluid (DEF) is used with diesel engines to reduce the amount of regulated emissions produced. The DEF system must be maintained for the vehicle to run properly. It is normal to hear the DEF system purge fluid back into the tank after the vehicle is shut off...

    GMC Terrain 2018-2025 Owners Manual: Warning Lights, Gauges, and Indicators


    Warning lights and gauges can signal that something is wrong before it becomes serious enough to cause an expensive repair or replacement. Paying attention to the warning lights and gauges could prevent injury. Some warning lights come on briefly when the engine is started to indicate they are working...

      Categories

      Tire Pressure Light

      GMC Terrain. Tire Pressure Light

      For vehicles with the Tire Pressure Monitor System (TPMS), this light comes on briefly when the engine is started. It provides information about tire pressures and the TPMS.

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