Automatic Headlamp System
When it is dark enough outside and the exterior lamps control is in the automatic position, the headlamps come on automatically. See Exterior Lamp Controls .

The vehicle has a light sensor located on top of the instrument panel. Make sure it is not covered, or the headlamps will be on when they are not needed.
The system may also turn on the headlamps when driving through a parking garage or tunnel.
See also:
Engine Compartment Overview
When you open the hood on the 4.2L L6 engine, here is what you will see:
A. Engine Air Cleaner/Filter.
B. Engine Coolant Recovery Tank.
C. Windshield Washer Fluid Reservoir.
D. Power Steering Fl ...
Passing
The driver of a vehicle about to pass another on a
two-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then
goes back into the right lane again. A simple
...
Security
OnStar provides services like Stolen
Vehicle Assistance, Remote Ignition
Block, and Roadside Assistance,
if the vehicle is equipped with these
services. OnStar can unlock the
vehicle doors r ...
