See also:

Compass Calibration Procedure
1. Before calibrating the compass, make sure the compass zone is set to the variance zone in which the vehicle is located. See “Compass Variance (Zone) Procedure” earlier in this section. Do not ...

Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is moving. Only set it when the vehicle is in P (Park). Press the vehicle information button until PRESS TO CHANGE COMPASS ZONE displays. Or, if the v ...

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 vehic ...