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 vehicle is equipped with the Tire Pressure Monitoring System. If a diagnostics check is needed between e-mails, push an Advisor can run a check., and an Advisor can run a check.

    See also:

    Automatic Transmission Shift Lock Control Function Check
    WARNING! When you are doing this inspection, the vehicle could move suddenly. If the vehicle moves, you or others could be injured. 1. Before starting this check, be sure there is enough r ...

    Tow/Haul Mode Light
    For vehicles with the Tow/Haul Mode feature, this light comes on when the Tow/Haul Mode has been activated. For more information, see Tow/Haul Mode  . ...

    Express Window Anti-Pinch Feature
    If any object is in the path of the window when the express-up is active, the window will stop at the obstruction and auto-reverse to a preset factory position. Weather conditions such as severe i ...