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:

    Services Specific to Canadian-Purchased Vehicles
    • Fuel Delivery: Reimbursement is approximately $5 Canadian. Diesel fuel delivery may be restricted. Propane and other fuels are not provided through this service. • Lock-Out Service: Vehicle re ...

    Instrument Panel Fuse Block
    The instrument panel fuse block is located under the instrument panel on the passenger side of the vehicle. Pull down on the cover to access the fuse block. Fuse Side The vehicle may not be equipp ...

    New for 2010
    GM has dropped the long-running 6.0-liter V-8 engine from the Sierra lineup, leaving the powerful 6.2-liter V-8 for heavy towing needs. The rest of the Sierra's eight-cylinder lineup benefits from ...