See also:

Tire Inspection
We recommend that the tires, including the spare tire, if the vehicle has one, be inspected for signs of wear or damage at least once a month. Replace the tire if: • The indicators at three or mor ...

Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehic ...

If No Steam is Coming from the Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the ENGINE OVERHEATED IDLE ENGINE message, along with a low coolant condition, can indicate a serious problem. If there is an engine overheat warning, but no stea ...