See also:

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 ...

Hydroplaning
Hydroplaning is dangerous. Water can build up under the vehicle's tires so they actually ride on the water. This can happen if the road is wet enough and you are going fast enough. When the ve ...

Engine Cooling System Messages
ENGINE HOT A/C (Air Conditioning) OFF This message displays when the engine coolant becomes hotter than the normal operating temperature. See Engine Coolant Temperature Gauge on page 5‑14. To ...