2006 GMC Yukon Owner's Manual - Page 175

The headlamp control has four positions: Turning the control to this position turns off the Daytime Running Lamps (DRL) and the automatic headlamps. AUTO (Automatic): Turning the control to this position puts the system into automatic headlamp mode. Turning the control to this position turns on the parking lamps, together with the following: 5 (Headlamps): 9 (Off): Turning the control to this position turns on the headlamps, together with the previously listed lamps and lights. You can switch your headlamps from high to low-beam by pushing the turn signal/high-beam lever towards the instrument panel. A circuit breaker protects your headlamps. If you have an electrical overload, your headlamps will flicker on and off. Have your headlamp wiring checked right away if this happens. ; (Parking Lamps): Sidemarker Lamps Taillamps License Plate Lamps Instrument Panel Lights Roof Marker Lamps (If Equipped) Headlamps on Reminder A reminder chime will sound when your headlamps or parking lamps are manually turned on and your ignition is off, in LOCK, ACCESSORY, or a door is open. To disable the chime, turn the light off then back on. 3-15