See also:

ENGINE OVERHEATED — IDLE ENGINE
This message displays when the engine coolant temperature is too hot. Stop and allow the vehicle to idle until it cools down. ...

Warranty
OnStar equipment may be warranted as part of the new-vehicle limited warranty. The manufacturer of the vehicle furnishes detailed warranty information. ...

Adding Equipment to the Outside of the Vehicle
Things added to the outside of the vehicle can affect the airflow around it. This can cause wind noise and can affect fuel economy and windshield washer performance. Check with your dealer/retail ...