2007 GMC Yukon Owner's Manual - Page 202

The DRL and automatic headlamp system will only be affected when the light sensor sees a change in lighting lasting longer than the delay. If you start your vehicle in a dark garage, the automatic headlamp system will come on immediately. Once you leave the garage, it will take approximately one minute for the automatic headlamp system to change to DRL if it is bright enough outside. During that delay, your instrument panel cluster may not be as bright as usual. Make sure your instrument panel brightness control is in the full bright position. See Instrument Panel Brightness on page 203. To idle your vehicle with the automatic headlamp system off, turn the control to the off position. You may be able to turn off your Automatic Headlamp System. See Daytime Running Lamps (DRL) on page 201 for more information. Your headlamps will also stay on after you exit the vehicle. You can program this feature using the Driver Information Center (DIC). See DIC Vehicle Customization (With DIC Buttons) on page 264. As with any vehicle, you should turn on the regular headlamp system when needed. Fog Lamps - (Fog Lamps): If your vehicle is equipped with fog lamps, it is located on the instrument panel to the left of the steering column. The fog lamps button is located below the dome lamp override button. Your ignition must be in RUN for the fog lamps to illuminate. To turn the fog lamps on, press the fog lamps button. A light will come on in the instrument panel cluster to let you know that the fog lamps are on. Press the button again to turn the fog lamps off. The ignition must be in RUN and the parking lamps must be on for your fog lamps to work. The fog lamps will go off while you change to high-beam headlamps. Some localities have laws that require the headlamps to be on along with the fog lamps. 202