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:

    Checking Things Under the Hood
    WARNING: An electric fan under the hood can start up and injure you even when the engine is not running. Keep hands, clothing, and tools away from any underhood electric fan. WARNING: Things t ...

    When to Add Engine Oil
    3.9L V6 Engine 4.6L V8 Engine If the oil is below the cross-hatched area at the tip of the dipstick, add at least one quart/liter of the recommended oil. This section explains what kind of o ...

    Starting the Vehicle Messages
    JUMP START ACTIVE WAIT TO START This message displays while performing an on-board jump start of the vehicle. See “Jump Starting (On-board with eAssist Only)” for more information. JUM ...