OnStar Services

See also:

Active Fuel Management®
Vehicles with V8 engines may have Active Fuel Management™. This system allows the engine to operate on either all or half of its cylinders, depending on the driving conditions. When less power is ...

Checking Engine Oil
It is a good idea to check the engine oil level at each fuel fill. In order to get an accurate reading, the vehicle must be on level ground. The engine oil dipstick handle is a yellow loop. See En ...

Transmission Messages
MANUAL SHIFT This message displays when the automatic transmission is in manual mode. See Manual Mode   for more information. TRANSMISSION HOT IDLE ENGINE Notice: Do not drive the vehic ...