2005 Buick Century Owner's Manual - Page 115

When it is dark enough outside, the front turn signal lamps will turn off and the vehicle's headlamps and parking lamps will turn on. The other lamps that come on with the headlamps will also come on. When it is bright enough outside, the headlamps will go off and the front turn signal lamps will come on. To idle the vehicle with the DRL and automatic headlamp control off, set the parking brake while the ignition is in OFF or LOCK. Then start the vehicle. The DRL, headlamps and parking lamps will stay off until the parking brake is released. To turn off the automatic headlamp feature when it is dark outside, move the exterior lamp control to the parking lamp position. The parking lamps will remain illuminated and the headlamps will turn off. The fog lamps will also go on if they were on previously. As with any vehicle, the regular headlamp system should be turned on when needed. Cornering Lamps The cornering lamps are designed to come on to provide additional light when a turn signal lamp is activated. Interior Lamps The interior lamps can be controlled, or automatically turn on or off under certain conditions. They are explained in the following text. Instrument Panel Brightness The instrument panel lights can be brightened or dimmed by turning the exterior lamps knob. Turning the control all the way clockwise turns on the courtesy lamps. Courtesy Lamps When any door is opened, several courtesy lamps come on to make it easier to enter and exit the vehicle. These lamps can also be turned on by turning the exterior lamps control all the way clockwise to MAX. 3-15