GMC Terrain: Setting Adaptive Cruise Control / Lighting Conditions Affecting ACC

The ACC front camera can be affected by poor lighting conditions, and ACC may have limited performance when:

  • There are changes in brightness, such as entering and exiting tunnels, bridges, and overpasses.
  • Low sun angles cause the camera to not detect objects, or it is more difficult to detect objects in the same traffic lane.
  • Lighting is poor in the evening or early morning
  • There are multiple changes in brightness or shadows along the vehicle roadway.
  • In a tunnel without the headlamps on, or in a tunnel when there is a vehicle in front that does not have its taillamps on.
  • Subjected to strong light from opposing lane traffic in the front of the vehicle, such as high-beam headlamps from oncoming traffic.

    Weather Conditions Affecting ACC

    If the interior temperature is extremely high, the instrument cluster may indicate that ACC is temporarily unavailable. This can be caused by extreme hot weather conditions with direct sunlight on the front camera...

    Accessory Installations and Vehicle Modifications

    Do not install or place any object around the front camera windshield area that would obstruct the front camera view. Do not install objects on top of the vehicle that overhang and obstruct the front camera, such as a canoe, kayak, or other items that can be transported on a roof rack system...

    Other information:

    GMC Terrain 2018-2025 Owners Manual: Tire Pressure Monitor System


    The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check tire pressure levels. The TPMS sensors monitor the air pressure in your tires and transmit tire pressure readings to a receiver located in the vehicle. Each tire, including the spare (if provided), should be checked monthly when cold and inflated to the inflation pressure recommended by the vehicle manufact..

    GMC Terrain 2018-2025 Owners Manual: Checking Coolant


    The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level mark is not visible, add a 50/50 mixture of clean, drinkable water and DEX-COOL coolant at the coolant surge..

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