Vehicle and Power Issues
OnStar services require a vehicle electrical system, wireless service, and GPS satellite technologies to be available and operating for features to function properly. These systems may not operate if the battery is discharged or disconnected.
See also:
New for 2010
GM has dropped the long-running 6.0-liter V-8 engine from the Sierra lineup,
leaving the powerful 6.2-liter V-8 for heavy towing needs. The rest of the
Sierra's eight-cylinder lineup benefits from ...
Weatherstrips
Apply silicone grease on weatherstrips to make them last longer, seal better, and not stick or squeak. See Recommended Fluids and Lubricants on page 11‑12. ...
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 ...