See also:

How the System Works
URPA comes on automatically when the shift lever is moved into R (Reverse). A single tone sounds to indicate the system is working. URPA operates only at speeds less than 8 km/h (5 mph). An obstacle ...

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 Q to try the call again or try again after driving a few miles into anoth ...

Automatic Dimming
If equipped with an automatic dimming mirror, the driver outside mirror adjusts for the glare of the headlamps behind you. See Automatic Dimming Rearview Mirror on page 2‑17. ...