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:
Diagnostics
OnStar Vehicle Diagnostics will
perform a vehicle check every
month. It will check the engine,
transmission, antilock brakes, and
major vehicle systems. It also
checks the tire pressures, if ...
What to Use
WARNING
Adding only plain water or some other liquid to the cooling system can be dangerous. Plain water and other liquids, can boil before the proper coolant mixture will.
The coolant warning sy ...
Services Specific to Canadian
Purchased Vehicles
• Fuel delivery: Reimbursement is approximately
$5 Canadian. Diesel fuel delivery may be restricted.
Propane and other fuels are not provided through
this service.
• Lock-Out Service: Vehicl ...
