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 OnStar Additional Information, and an Advisor can run a check.

    See also:

    If the Off Indicator is Lit for an Adult-Size Occupant
    If a person of adult-size is sitting in the right front passenger seat, but the off indicator is lit, it could be because that person is not sitting properly in the seat. If this happens, use the fo ...

    Fuel Economy Mode
    Vehicles with a 2.4L engine have a Fuel Economy Mode. When engaged, fuel economy mode can improve the vehicle's fuel economy. Press the “eco” (economy) button by the shift lever to turn t ...

    Global Positioning System (GPS)
    • Obstruction of the GPS can occur in a large city with tall buildings; in parking garages; around airports; in tunnels, underpasses, or parking garages; or in an area with very dense trees. If GPS ...