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:
Exterior
The Yukon has a one-piece grille and taller headlights than its sister Tahoe,
with jewel-like bezels and a wider, lower air dam. The rest of the body features
blocky fenders, long rear-quarter win ...
Safety
Standard safety features include:
Four-wheel antilock brakes
Electronic stability system
Side curtain and side-impact airbags ...
Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect vehicle performance and safety, including such things as airbags, braking, stability, ride and handling, emissions syste ...