Service Bulletins

Service Bulletins give additional technical service information needed to knowledgeably service General Motors cars and trucks.

Each bulletin contains instructions to assist in the diagnosis and service of the vehicle.

    See also:

    Horn
    Press on the steering wheel pad to sound the horn. ...

    Ignition Positions (Key Access)
    The ignition switch can be turned to four different positions. To shift out of P (Park), the ignition switch must be in ON/RUN or ACC/ACCESSORY and the brake pedal must be applied. Notice: ...

    Using Voice Commands During a Planned Route
    Cancel Route 1. Push . System responds: “OnStar ready,” then a tone. Say “Cancel route.” System responds: “Would you like to cancel route directions to your destination?” 2. Say “Yes.” System re ...