OnStar

See also:

Automatic Transmission
Move the shift lever to P (Park) or N (Neutral). The engine will not start in any other position. To restart the engine when the vehicle is already moving, use N (Neutral) only. If the vehicl ...

Transmission Messages
SERVICE TRANSMISSION This message displays if there is a problem with the transmission. See your dealer. SHIFT DENIED This message displays when using the Driver Shift Control (DSC) and a ...

Transmission Messages
DIFFERENTIAL HOT, REDUCE SPEED (CTS-V ONLY) This message displays and a chime sounds if the differential fluid temperature exceeds 150°C (300°F). Driving aggressively or at high speeds can ...