Unable to Connect to OnStar Message

GMC Sierra / GMC Sierra Owners Manuals / OnStar / OnStar Additional Information / Unable to Connect to OnStar Message

If there is limited cellular coverage or the cellular network has reached maximum capacity, this message may come on. Push Vehicle and Power Issues to try the call again or try again after driving a few miles into another cellular area.

    See also:

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    Checking Brake Fluid
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