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 another cellular area. 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.
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Under the Hood
Mechanical features include:
185-horsepower, 2.9-liter inline-four-cylinder with aluminum block and
cylinder head, dual overhead camshafts and four valves per cylinder that makes
190 pounds-feet ...
Going & Stopping
The biggest drawback I found with the Yukon was the powertrain. A
380-horsepower, 6.2-liter V-8 is standard in the Denali, but it was sluggish in
almost every passing situation I could simulate. T ...
Trailer Sway Control (TSC)
Non-hybrid vehicles with StabiliTrak have a Trailer Sway Control (TSC) feature. If the vehicle is towing a trailer and the system detects that the trailer is swaying, the vehicle brakes are applied wi ...