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 
to try the
call again or try again after driving a
few miles into another cellular area.
See also:
How to Check Lubricant
To get an accurate reading, the vehicle should be on a level surface.
A. Fill Plug
B. Drain Plug
When the differential is cold, add enough lubricant to raise the level
from 0mm (0 in) to 3. ...
Engine Compartment Fuse Block
The Engine Compartment Fuse Block is located in the engine compartment, on the
driver side of the vehicle. Lift the cover for access to the fuse/relay block.
If the vehicle is a hybrid, see the h ...
Cellular and GPS Antennas
Avoid placing items over or near
the antenna to prevent blocking
cellular and GPS signal reception.
Cellular reception is required for
OnStar to send remote signals to
the vehicle. ...